Add basic tests for refactored files

Those were hooks just used in one place. We move them directly into
their component.
This is acceptable because the disconnect banner needs a new appraoch
when not having a syncing clinet but just a matrixBackend.

.github/workflows/blocked.yaml

@@ -14,7 +14,7 @@ permissions:
 jobs:
   prevent-blocked:
     name: Prevent blocked
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     permissions:
       pull-requests: read
     steps:

.github/workflows/build-and-publish-docker.yaml

@@ -17,7 +17,7 @@ env:
 jobs:
   build_and_deploy:
     name: Build & publish docker
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     permissions:
       contents: write # required to upload release asset
       packages: write # needed for publishing packages to GHCR

.github/workflows/build-element-call.yaml

@@ -29,7 +29,7 @@ on:
 jobs:
   build:
     name: Build Element Call
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     steps:
       - name: Checkout code
         uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4

.github/workflows/build.yaml

@@ -25,7 +25,7 @@ jobs:
     # Deploy main branch to call.element.dev after build completes
     if: github.ref == 'refs/heads/main'
     needs: build_full_element_call
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     steps:
       - name: Deploy to call.element.dev
         uses: actions/github-script@d7906e4ad0b1822421a7e6a35d5ca353c962f410 # v6
@@ -92,7 +92,7 @@ jobs:
   build_storybook:
     name: Build Storybook
     if: contains(github.event.pull_request.labels.*.name, 'storybook build')
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     steps:
       - name: Checkout code
         uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4

.github/workflows/changelog-label.yml

@@ -13,7 +13,7 @@ permissions:
 
 jobs:
   pr-changelog-label:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     steps:
       - uses: yogevbd/enforce-label-action@a3c219da6b8fa73f6ba62b68ff09c469b3a1c024 # 2.2.2
         with:

.github/workflows/claude.yaml

@@ -13,7 +13,7 @@ jobs:
     name: Review
     # Only run on labelling and skip forks.
     if: github.event.label.name == 'Claude-Review' && github.event.pull_request.head.repo.full_name == github.repository
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     steps:
       - name: Checkout code
         uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4.4.0

.github/workflows/deploy-to-netlify.yaml

@@ -32,7 +32,7 @@ on:
 
 jobs:
   deploy:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     permissions:
       deployments: write
     environment: Netlify

.github/workflows/lint.yaml

@@ -10,7 +10,7 @@ on:
 jobs:
   lint:
     name: Lint, format & type check
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     steps:
       - name: Checkout code
         uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4

.github/workflows/pr-deploy.yaml

@@ -17,7 +17,7 @@ jobs:
       github.event.workflow_run.conclusion == 'success' &&
       github.event.workflow_run.event == 'pull_request' &&
       github.event.workflow_run.head_repository.full_name == github.repository
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     outputs:
       pr_number: ${{ steps.prdetails.outputs.pr_id }}
       pr_data_json: ${{ steps.prdetails.outputs.data }}

.github/workflows/publish-component.yaml

@@ -17,7 +17,7 @@ permissions: {}
 jobs:
   versioning:
     name: Versioning
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     outputs:
       DRY_RUN: ${{ steps.dry_run.outputs.DRY_RUN }}
       PREFIXED_VERSION: ${{ steps.prefixed_version.outputs.PREFIXED_VERSION }}
@@ -59,7 +59,7 @@ jobs:
   publish_npm:
     needs: versioning
     name: Publish NPM
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     outputs:
       ARTIFACT_VERSION: ${{ steps.artifact_version.outputs.ARTIFACT_VERSION }}
     permissions:
@@ -111,7 +111,7 @@ jobs:
     needs: [versioning, publish_npm]
     if: ${{ needs.versioning.outputs.DRY_RUN == 'false' }}
     name: Update release notes
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     # Shared with publish-embedded-packages.yaml, which appends to the same release: two
     # appends at once would each write back the body without the other's section
     concurrency:

.github/workflows/publish-embedded-packages.yaml

@@ -14,7 +14,7 @@ on:
 jobs:
   versioning:
     name: Versioning
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     outputs:
       DRY_RUN: ${{ steps.dry_run.outputs.DRY_RUN }}
       PREFIXED_VERSION: ${{ steps.prefixed_version.outputs.PREFIXED_VERSION }}
@@ -76,7 +76,7 @@ jobs:
     needs: [build_element_call, versioning]
     if: always()
     name: Publish tarball
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     permissions:
       contents: write # required to upload release asset
     steps:
@@ -107,7 +107,7 @@ jobs:
     needs: [build_element_call, versioning]
     if: always()
     name: Publish NPM
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     outputs:
       ARTIFACT_VERSION: ${{ steps.artifact_version.outputs.ARTIFACT_VERSION }}
     permissions:
@@ -152,7 +152,7 @@ jobs:
     needs: [build_element_call, versioning]
     if: always()
     name: Publish Android AAR
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     outputs:
       ARTIFACT_VERSION: ${{ steps.artifact_version.outputs.ARTIFACT_VERSION }}
     permissions:
@@ -212,7 +212,7 @@ jobs:
     needs: [build_element_call, versioning]
     if: always()
     name: Publish SwiftPM Library
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     outputs:
       ARTIFACT_VERSION: ${{ steps.artifact_version.outputs.ARTIFACT_VERSION }}
     permissions:
@@ -282,7 +282,7 @@ jobs:
     needs: [versioning, publish_npm, publish_android, publish_ios]
     if: always()
     name: Update release notes
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     # Shared with publish-component.yaml, which appends to the same release: two appends
     # at once would each write back the body without the other's section
     concurrency:

.github/workflows/publish.yaml

@@ -23,7 +23,7 @@ jobs:
     needs: build_element_call
     if: always()
     name: Publish tarball
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     permissions:
       contents: write # required to upload release asset
       packages: write
@@ -68,7 +68,7 @@ jobs:
   add_docker_release_note:
     needs: publish_docker
     name: Add docker release note
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     steps:
       - name: Add release note
         uses: softprops/action-gh-release@3bb12739c298aeb8a4eeaf626c5b8d85266b0e65 # v2

.github/workflows/test.yaml

@@ -25,7 +25,7 @@ on:
 jobs:
   vitest:
     name: Run unit tests
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     steps:
       - name: Checkout code
         uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
@@ -71,10 +71,27 @@ jobs:
           flags: unittests
           fail_ci_if_error: true
   playwright:
-    name: Run end-to-end tests
+    name: Run end-to-end tests (${{ matrix.part }})
     if: ${{ !inputs.disable_e2e_tests }}
     timeout-minutes: 60
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
+    # We manually shard the tests across runners. Playwright's own shards cut
+    # the list of tests into equal counts in file order, which would leave the
+    # widget suite, the slowest tests by far, together at the end.
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - part: chromium-1
+            args: --project=chromium --shard=1/2
+          - part: chromium-2
+            args: --project=chromium --shard=2/2
+          - part: widget-1
+            args: --project=widget --shard=1/2
+          - part: widget-2
+            args: --project=widget --shard=2/2
+          - part: firefox-mobile
+            args: --project=firefox --project=mobile
     steps:
       - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
         with:
@@ -107,17 +124,64 @@ jobs:
         run: pnpm playwright install --with-deps
       - name: Run backend components
         run: |
+          # Make sure the directory for the embedded build exists as Docker might
+          # create it with wrong access rights otherwise.
+          mkdir -p embedded/web/dist
           docker compose -f docker-compose-dev.yml -f docker-compose-playwright.yml pull
           docker compose -f docker-compose-dev.yml -f docker-compose-playwright.yml up -d
           docker ps
       - name: Run Playwright tests
         env:
           USE_DOCKER: 1
-        run: pnpm exec playwright test
+          ARGS: ${{ matrix.args }}
+        # Unquoted on purpose: the part's arguments are several words
+        run: pnpm exec playwright test $ARGS
       - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         if: ${{ !cancelled() }}
+        with:
+          name: blob-report-${{ matrix.part }}
+          path: blob-report
+          if-no-files-found: error
+          # Only read by the merge below.
+          retention-days: 1
+
+  e2e_report:
+    # Combines the blobs into a single HTML report and blocks PRs on failure.
+    name: Run end-to-end tests
+    needs: playwright
+    if: ${{ always() && !inputs.disable_e2e_tests }}
+    runs-on: ubuntu-24.04
+    steps:
+      - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
+        with:
+          # Inside a called workflow, github.repository is the caller so we need to make sure to still check out the EC repo here.
+          repository: ${{ inputs.matrix-js-sdk-sha && 'element-hq/element-call' || github.repository }}
+          persist-credentials: false
+      - name: Enable Corepack
+        run: corepack enable
+      - uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
+        with:
+          cache: "pnpm"
+          node-version-file: ".node-version"
+      - name: Install dependencies
+        run: scripts/layered.sh --ignore-pnpmfile
+        env:
+          PR_HEAD_REPO_OWNER: ${{ github.event.pull_request.head.repo.owner.login }}
+          JS_SDK_GITHUB_BASE_REF: ${{ inputs.matrix-js-sdk-sha }}
+      - name: Download the parts' reports
+        uses: actions/download-artifact@d3f86a106a0bac45b974a628896c90dbdf5c8093 # v4
+        with:
+          pattern: blob-report-*
+          path: all-blob-reports
+          merge-multiple: true
+      - name: Merge into one HTML report
+        run: pnpm exec playwright merge-reports --reporter html ./all-blob-reports
+      - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         with:
           name: html-report
           path: playwright-report
           if-no-files-found: error
           retention-days: 4
+      - name: Fail on a failed part
+        if: ${{ needs.playwright.result != 'success' }}
+        run: exit 1

.github/workflows/translations-download.yaml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   download:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     permissions:
       contents: read
 

.github/workflows/translations-upload.yaml

@@ -8,7 +8,7 @@ on:
 
 jobs:
   upload:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     permissions:
       contents: read
 

.github/workflows/zizmor.yml

@@ -10,7 +10,7 @@ permissions: {}
 jobs:
   zizmor:
     name: Run zizmor 🌈
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     permissions:
       security-events: write # Required for upload-sarif (used by zizmor-action) to upload SARIF files.
     steps:

README.md

@@ -221,119 +221,68 @@ See also:
 
 - [Developing with linked packages](./docs/linking.md)
 
-#### Element Call as a component (experimental)
+#### Element Call as a component
 
-Element Call can also be embedded directly into another React application
-rather than being loaded in an iframe as a widget. `pnpm build:component`
-builds it as a library into `component/dist` (the bundle, its stylesheet and
-type declarations), and
+Element Call can be rendered inside another React app instead of an iframe.
+The host supplies its own Matrix client, and the call stays inside the element
+it is mounted in.
 
-```sh
-pnpm dev:component
-```
-
-serves a harness on port 3001 that stands in for such an application: it signs
-in twice against the development backend and shows two calls side by side, in
-resizable boxes, with page furniture of its own around them. Use it to see how
-Element Call behaves when it does not own the page — the size it is given,
-whether it stays inside its container, and what it says to its host, which is
-logged along the bottom. The harness is served with the same development
-certificate as the app, so unless the development CA is trusted, the browser
-needs a certificate exception for `https://localhost:3001` as well (see the
-note under [Backend](#backend)). It reads the same `public/config.json` as
-`pnpm dev` if one exists, and runs with Element Call's defaults otherwise.
-
-The call lays itself out for the size of the element it is mounted in, not the
-window: a host that shrinks the container to a corner of its page gets the
-picture-in-picture layout, just as a host that shrank the whole iframe used to.
-The breakpoints in the stylesheets the component uses are
-`@container element-call` queries against its root element for the same reason;
-for the standalone app the root is the page, so they mean what the media queries
-they replaced did. (The standalone-only views, such as the home and login pages,
-still use plain media queries, since the component never shows them.)
-
-The component's stylesheet is confined to the element it is mounted in: the
-build rewrites every selector so that it matches only Element Call's root or
-what is inside it, with `html`, `body` and `:root` standing for that root (see
-`component/build/scopeStylesToRoot.ts`). A host's own page keeps its styles,
-and Element Call brings its own fonts and design tokens along.
-
-The component speaks every language the app does. English is bundled in; the
-other locales are split into chunks the host's bundler loads the first time
-they are needed. It starts in the browser's language, and follows the host's
-own language setting through the `language` prop (`supportedLanguages` lists
-the tags it accepts, and anything else falls back to its base language or to
-English). The `theme` prop works the same way and takes the same values as the
-widget's `theme` URL parameter: `light`, `dark`, `light-high-contrast` or
-`dark-high-contrast`. Both can change while a call is running without
-disturbing it.
-
-A host must call and await `initializeElementCall(config)` once before
-rendering the component: it loads the `Intl` polyfills, applies the
-deployment-wide `config.json`-style configuration and sets up translations.
-The component itself takes the host's `client` and the `roomId` to call in, an
-`intent` saying what the user asked for (which decides whether to show the
-lobby, ring, and so on), an optional `config` overriding what the intent
-implies, and an optional `hostBridge` through which Element Call tells the host
-that the user has joined or hung up, that it wants to stay on screen, and so
-on. The host makes its own requests (`join`, `hangUp`, `setDeviceMute`) through
-the handle exposed on `ref`. The full API is documented in the type declarations
-(`component/index.tsx` and `component/host.ts`).
-
-A few things differ from the widget on purpose: the component draws a solid
-background rather than a gradient unless told otherwise, never offers to edit
-the user's profile (the account is the host's), scopes its keyboard shortcuts to
-its own root element so that several instances can share a page, and only shows
-its own post-call and error screens when the host has not supplied a `close()`
-callback; with one, it asks the host to unmount it instead. The
-[global JS controls](./docs/controls.md) on `window` are unchanged and remain
-page-wide, so with several instances on one page they apply to all of them.
-
-Each release publishes the package to npm, with the same version as the release:
+##### Install
 
 ```sh
 npm install @element-hq/element-call-component
 ```
 
-To use an unreleased commit, a host can instead install it as a git dependency
-on the `component` directory of this repository,
+Releases publish the package with the same version as Element Call. For an
+unreleased commit, depend on this repository directly:
 
 ```json
 "@element-hq/element-call-component": "github:element-hq/element-call#main&path:/component"
 ```
 
-whose `prepare` script runs the build on install. That build needs pnpm (via
-Corepack) on the host's machine, runs a full `pnpm install` of this repository,
-since it inherits the `--max-old-space-size` setting of
-the app build; the host's pnpm also has to allow it to run at all
-(`allowBuilds` in its `pnpm-workspace.yaml`). Note that `component/` is a pnpm
-project of its own for this reason, so pnpm commands run from inside that
-directory target it rather than the repository; run them from the repository
-root. The host imports the component from
-`@element-hq/element-call-component` and the stylesheet from
-`@element-hq/element-call-component/style.css`, and has to provide `react`,
-`react-dom`, `matrix-js-sdk`, `@vector-im/compound-web` and
-`@vector-im/compound-design-tokens` itself, since the bundle leaves them
-external.
-Compound's stylesheet are the host's to load too: the component shares
-the host's copy of Compound, (required for example for tooltips)
+This builds on install, so the host needs pnpm (via Corepack) and must allow
+the build (`allowBuilds` in its `pnpm-workspace.yaml`).
 
-The component is large, and a host will usually load it lazily, only once a
-call is shown. Everything a host needs in order to talk about a call before
-then is also exported
-from `@element-hq/element-call-component/api` (a small entry point that does not
-load the component).
+##### Use
 
-- props and the types they are made of
-- the handle
-- the host bridge
-- `UserIntent`
-- `HeaderStyle`
-- `BackgroundStyle` enums
-- `configurationForIntent`, the defaults each intent implies
-  Import from it wherever a value such as
-  `BackgroundStyle.Solid` is needed on a path that must stay light; the main
-  entry point re-exports all of it too.
+1. Provide the externals yourself: `react`, `react-dom`, `matrix-js-sdk`,
+   `@vector-im/compound-web`, `@vector-im/compound-design-tokens`, and
+   Compound's stylesheet.
+2. Import `@element-hq/element-call-component/style.css`.
+3. Await `initializeElementCall(config)` once before rendering.
+4. Render the component with `client`, `roomId` and an `intent`; optionally
+   pass `config`, `hostBridge`, `language` and `theme` (both can change
+   mid-call). Control it through the `ref` handle (`join`, `hangUp`,
+   `setDeviceMute`).
+
+Load the component lazily. Types, enums and `configurationForIntent` are
+available without it from `@element-hq/element-call-component/api`. The full
+API is in `component/index.tsx`, `component/api.ts` and `component/host.ts`.
+
+##### How it differs from the widget
+
+- It lays out for its container, not the window: a small container gets the
+  picture-in-picture layout.
+- Its styles and keyboard shortcuts are scoped to its root, so the host page is
+  untouched and several instances can share a page. The
+  [global JS controls](./docs/controls.md) stay page-wide.
+- It draws a solid background by default and never offers profile editing.
+- If the host bridge implements `close()`, it asks to be unmounted instead of
+  showing its own post-call and error screens.
+- Sounds, images and the MediaPipe runtime are separate files the host's
+  bundler copies (webpack 5, Vite, Rollup); MediaPipe is fetched only when a
+  background effect is first used.
+
+##### Develop
+
+- `pnpm build:component` builds the library into `component/dist`.
+- `pnpm dev:component` serves a test host on `https://localhost:3001`: two
+  calls side by side in resizable boxes, with host messages logged at the
+  bottom. It uses the development backend, `public/config.json` if present,
+  and needs the same certificate exception as `pnpm dev` (see
+  [Backend](#backend)).
+- Run pnpm commands from the repository root; `component/` is its own pnpm
+  project.
 
 ### Backend
 

component/index.tsx

@@ -73,6 +73,7 @@ import {
 } from "../src/UrlParams";
 import { MediaDevicesContext } from "../src/MediaDevicesContext";
 import { AppViewModel } from "../src/state/AppViewModel";
+import { hostClientSession } from "../src/state/ClientSession";
 import { ObservableScope } from "../src/state/ObservableScope";
 import { BackgroundEffectsProvider } from "../src/tracks/BackgroundEffectsContext";
 import { Config } from "../src/config/Config";
@@ -189,20 +190,25 @@ export const ElementCall: FC<ElementCallProps> = ({
     [roomId, intent, stableConfig],
   );
 
-  // Created in an effect so that the scope it lives in ends when the component
-  // is unmounted (or these options change), rather than keeping its device
-  // observers running for the rest of the page's life. Null until then, which
-  // is one render.
   const { controlledAudioDevices, callIntent } = params;
   const [vm, setVm] = useState<AppViewModel | null>(null);
   useEffect(() => {
     const scope = new ObservableScope();
-    setVm(new AppViewModel(scope, { controlledAudioDevices, callIntent }));
+    setVm(
+      new AppViewModel(
+        scope,
+        { controlledAudioDevices, callIntent },
+        // The host owns the client. We create a clientSession wrapping the host client.
+        hostClientSession(client),
+        // The host owns the session too, so there is nothing to manage here
+        null,
+      ),
+    );
     return (): void => {
       setVm(null);
       scope.end();
     };
-  }, [controlledAudioDevices, callIntent]);
+  }, [controlledAudioDevices, callIntent, client]);
 
   const room = client.getRoom(roomId);
   const rtcSession = useMemo(
@@ -250,7 +256,7 @@ export const ElementCall: FC<ElementCallProps> = ({
                     >
                       <Decoration>
                         <TooltipProvider>
-                          <ClientProvider client={client}>
+                          <ClientProvider session={vm.clientSession}>
                             <MediaDevicesContext value={vm.mediaDevices}>
                               <BackgroundEffectsProvider
                                 effects={vm.backgroundEffects}

docker-compose-dev.yml

@@ -3,7 +3,7 @@ networks:
 
 services:
   auth-service:
-    image: ghcr.io/element-hq/lk-jwt-service:0.8.0
+    image: ghcr.io/element-hq/lk-jwt-service:0.10.0
     pull_policy: always
     hostname: auth-server
     environment:
@@ -33,7 +33,7 @@ services:
       - ecbackend
 
   auth-service-1:
-    image: ghcr.io/element-hq/lk-jwt-service:0.8.0
+    image: ghcr.io/element-hq/lk-jwt-service:0.10.0
     pull_policy: always
     hostname: auth-server-1
     environment:

docker-compose-playwright.yml

@@ -19,7 +19,12 @@ services:
       - ./backend/playwright_homeserver-othersite.yaml:/data/cfg/homeserver.yaml:Z
   element-web:
     # Pin to a SHA so that upstream cannot break our tests. Renovate handles regular updates.
-    image: ghcr.io/element-hq/element-web:develop@sha256:e063472b6bdf6d0bfa1d43dfa4ef7effee1efd2c9684daee665d1bedfe746a47
+    image: ghcr.io/element-hq/element-web:develop@sha256:72791f0b2541208f8f7edd9c6b5a7eaf88accd8ed1f0c4db1bc62bfe18eb90fe
   element-web-1:
     # Pin to a SHA so that upstream cannot break our tests. Renovate handles regular updates.
-    image: ghcr.io/element-hq/element-web:develop@sha256:e063472b6bdf6d0bfa1d43dfa4ef7effee1efd2c9684daee665d1bedfe746a47
+    image: ghcr.io/element-hq/element-web:develop@sha256:72791f0b2541208f8f7edd9c6b5a7eaf88accd8ed1f0c4db1bc62bfe18eb90fe
+    volumes:
+      # The other site opens the embedded package under test in place of the
+      # copy its image bundles (the first site opens the dev server's app.
+      # Built by the Playwright run (see build.setup.ts).
+      - ./embedded/web/dist:/app/widgets/element-call:ro,Z

docs/agents/architecture.md

@@ -10,11 +10,6 @@
 - Owning a resource: a class taking the scope in its constructor — `MediaDevices`,
   `MuteStates`, `TileStore`, `Publisher`, `Connection`. Both styles are current;
   don't convert one to the other in passing.
-- A factory's positional parameters are what the thing is made of: required, no
-  sensible default. Its trailing `options` bag is how the host wants it to
-  behave: every field optional, each defaulting to standalone behaviour, so `{}`
-  works. A value with no default is never an option; a test seam is never an
-  option either — mock the dependency it comes from. See `createCallViewModel$`.
 - `foo$` is an observable. `Behavior<T>`, an observable with a current value, is
   the default for anything a view reads.
 

docs/agents/testing.md

@@ -34,6 +34,10 @@ translations. The browser is Playwright's, so a fresh clone needs
 
 ## End-to-end
 
+The Element Web instance `HOST1` opens the app the dev server serves. The instance
+`HOST2` (the other site) opens the embedded package as a host ships it. This package
+is built by the `build-embedded` setup project and mounted in `docker-compose-playwright.yml`.
+
 - `playwright/*.spec.ts` — standalone, on Chromium and Firefox.
 - `playwright/widget/` — widget mode, where cross-context bugs surface.
 - `playwright/component/` — the component in a host page, via the harness on port

package.json

@@ -107,7 +107,7 @@
     "livekit-client": "^2.18.1",
     "lodash-es": "^4.17.21",
     "loglevel": "^1.9.1",
-    "matrix-js-sdk": "github:matrix-org/matrix-js-sdk#a9ef09fbf2f1644c8663d0aeaf6a921cd16e7b01",
+    "matrix-js-sdk": "github:matrix-org/matrix-js-sdk#dc8610e796c92553c658300a4882dde961a0678a",
     "matrix-widget-api": "^1.18.0",
     "node-stdlib-browser": "^1.3.1",
     "normalize.css": "^8.0.1",

playwright.config.ts

@@ -26,6 +26,19 @@ process.env.NODE_EXTRA_CA_CERTS = join(
   "backend/dev_tls_local-ca.crt",
 );
 
+const desktopChrome = {
+  ...devices["Desktop Chrome"],
+  permissions: ["clipboard-write", "clipboard-read", "microphone", "camera"],
+  ignoreHTTPSErrors: true,
+  launchOptions: {
+    args: [
+      "--use-fake-ui-for-media-stream",
+      "--use-fake-device-for-media-stream",
+      "--mute-audio",
+    ],
+  },
+};
+
 /**
  * See https://playwright.dev/docs/test-configuration.
  */
@@ -43,11 +56,11 @@ export default defineConfig({
    * Reporter to use. See https://playwright.dev/docs/test-reporters
    *
    * On CI, `list` prints a line per test as it finishes, which keeps the job
-   * log moving; `github` annotates failures on the PR; `html` is uploaded as
-   * an artifact and must never try to open a browser there.
+   * log moving; `github` annotates failures on the PR; the `blob` format is
+   * uploaded by sharded CI runs and combined into a HTML report by the workflow.
    */
   reporter: process.env.CI
-    ? [["list"], ["github"], ["html", { open: "never" }]]
+    ? [["list"], ["github"], ["blob"]]
     : [["list"], ["html"]],
   /* Stop a broken run early on CI instead of waiting out every retry. */
   maxFailures: process.env.CI ? 5 : undefined,
@@ -63,29 +76,28 @@ export default defineConfig({
   },
   /* Configure projects for major browsers */
   projects: [
+    {
+      // Builds the embedded package into the directory the other site's
+      // Element Web container serves it from (see docker-compose-playwright.yml).
+      name: "build-embedded",
+      testMatch: "**/widget/embedded/build.setup.ts",
+    },
     {
       name: "chromium",
-      testIgnore: "**/mobile/**",
-      use: {
-        ...devices["Desktop Chrome"],
-        permissions: [
-          "clipboard-write",
-          "clipboard-read",
-          "microphone",
-          "camera",
-        ],
-        ignoreHTTPSErrors: true,
-        launchOptions: {
-          args: [
-            "--use-fake-ui-for-media-stream",
-            "--use-fake-device-for-media-stream",
-            "--mute-audio",
-          ],
-        },
-      },
+      testIgnore: ["**/mobile/**", "**/widget/**"],
+      use: desktopChrome,
+    },
+    {
+      // Element Call as a widget in Element Web, on Chromium. This uses its
+      // own project so that it can be sharded on CI.
+      name: "widget",
+      dependencies: ["build-embedded"],
+      testMatch: "**/widget/**/*.@(spec|test).ts",
+      use: desktopChrome,
     },
     {
       name: "firefox",
+      dependencies: ["build-embedded"],
       testIgnore: "**/mobile/**",
       use: {
         ...devices["Desktop Firefox"],

playwright/fixtures/widget-user.ts

@@ -127,13 +127,14 @@ export const widgetTest = test.extend<MyFixtures>({
    * Provide a way to add additional users within a test.
    * The returned user will be registered on the default homeserver, the name will be made unique by appending a timestamp.
    */
-  addUser: async ({ browser }, use) => {
+  addUser: async ({ browser }, use, testInfo) => {
     await use(
       async (
         username: string,
         host: string = HOST1,
       ): Promise<UserBaseFixture> => {
-        const uniqueSuffix = Date.now();
+        // Tests in parallel workers can reach this in the same millisecond.
+        const uniqueSuffix = `${Date.now()}_${testInfo.parallelIndex}`;
         const { page, clientHandle, mxId } = await TestHelpers.registerUser(
           browser,
           `${username.toLowerCase()}_${uniqueSuffix}`,

playwright/widget/embedded/build.setup.ts

@@ -0,0 +1,20 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { test as setup } from "@playwright/test";
+import { execFileSync } from "node:child_process";
+import { mkdirSync } from "node:fs";
+
+const EMBEDDED_DIST = "embedded/web/dist";
+
+setup("build the embedded package", () => {
+  setup.setTimeout(10 * 60 * 1000);
+  mkdirSync(EMBEDDED_DIST, { recursive: true });
+  execFileSync("pnpm", ["build:embedded", "--outDir", EMBEDDED_DIST], {
+    stdio: "inherit",
+  });
+});

playwright/widget/embedded/config-json.spec.ts

@@ -0,0 +1,56 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { expect, type Route } from "@playwright/test";
+
+import { widgetTest } from "../../fixtures/widget-user.ts";
+import { HOST2, TestHelpers } from "../test-helpers.ts";
+
+/** Where the other site's Element Web serves the embedded package from */
+const CONFIG_JSON = "**/widgets/element-call/config.json";
+
+const HOST_ANSWERS: Record<string, (route: Route) => Promise<void>> = {
+  "a 404": async (route) => route.fulfill({ status: 404 }),
+  "a failed fetch": async (route) => route.abort("failed"),
+  "an HTML page": async (route) =>
+    route.fulfill({
+      status: 200,
+      contentType: "text/html",
+      body: "<!doctype html><title>Element</title>",
+    }),
+};
+
+widgetTest.skip(
+  ({ browserName }) => browserName === "firefox",
+  "The widget suite does not run on Firefox, see the other specs here",
+);
+
+for (const [answer, respond] of Object.entries(HOST_ANSWERS)) {
+  widgetTest(
+    `reaches the lobby when config.json gets ${answer}`,
+    async ({ addUser }) => {
+      const { page } = await addUser("Brooks", HOST2);
+      await TestHelpers.createRoom("Config Room", page);
+
+      let answered = 0;
+      await page.route(CONFIG_JSON, async (route) => {
+        answered++;
+        await respond(route);
+      });
+
+      await TestHelpers.startCallInCurrentRoom(page);
+
+      await expect(
+        page
+          .locator('iframe[title="Element Call"]')
+          .contentFrame()
+          .getByTestId("lobby_joinCall"),
+      ).toBeVisible({ timeout: 15000 });
+      expect(answered).toBeGreaterThan(0);
+    },
+  );
+}

playwright/widget/test-helpers.ts

@@ -144,7 +144,11 @@ export class TestHelpers {
 
     await this.dismissStartupToasts(page);
 
-    await TestHelpers.setDevToolElementCallDevUrl(page);
+    // The other site's Element Web opens the embedded package it serves itself
+    // (see docker-compose-playwright.yml), not the dev server's app.
+    if (host !== HOST2) {
+      await TestHelpers.setDevToolElementCallDevUrl(page);
+    }
 
     const clientHandle = await page.evaluateHandle(() =>
       window.mxMatrixClientPeg.get(),

pnpm-lock.yaml

@@ -191,8 +191,8 @@ importers:
         specifier: ^1.9.1
         version: 1.9.2
       matrix-js-sdk:
-        specifier: github:matrix-org/matrix-js-sdk#a9ef09fbf2f1644c8663d0aeaf6a921cd16e7b01
-        version: https://codeload.github.com/matrix-org/matrix-js-sdk/tar.gz/a9ef09fbf2f1644c8663d0aeaf6a921cd16e7b01
+        specifier: github:matrix-org/matrix-js-sdk#dc8610e796c92553c658300a4882dde961a0678a
+        version: https://codeload.github.com/matrix-org/matrix-js-sdk/tar.gz/dc8610e796c92553c658300a4882dde961a0678a
       matrix-widget-api:
         specifier: ^1.18.0
         version: 1.20.0
@@ -4734,8 +4734,8 @@ packages:
   matrix-events-sdk@0.0.1:
     resolution: {integrity: sha512-1QEOsXO+bhyCroIe2/A5OwaxHvBm7EsSQ46DEDn8RBIfQwN5HWBpFvyWWR4QY0KHPPnnJdI99wgRiAl7Ad5qaA==}
 
-  matrix-js-sdk@https://codeload.github.com/matrix-org/matrix-js-sdk/tar.gz/a9ef09fbf2f1644c8663d0aeaf6a921cd16e7b01:
-    resolution: {gitHosted: true, integrity: sha512-ZAhn/zB44MgrXqUzi9ffSFcmZY3+2nx7bEgfEJR7chYDFyT/XmlmfCJx7Ar4rOTAYZJRVnMxrEwiEHGDapUi0Q==, tarball: https://codeload.github.com/matrix-org/matrix-js-sdk/tar.gz/a9ef09fbf2f1644c8663d0aeaf6a921cd16e7b01}
+  matrix-js-sdk@https://codeload.github.com/matrix-org/matrix-js-sdk/tar.gz/dc8610e796c92553c658300a4882dde961a0678a:
+    resolution: {gitHosted: true, integrity: sha512-Ldt/VkCzBtre6m1cn0FqgrzRV0GrgWIoARgQUQO58ef2Edu2ERFCINPzp/psFS5RwoN3RIy9Rm4oPVc1ATkEWA==, tarball: https://codeload.github.com/matrix-org/matrix-js-sdk/tar.gz/dc8610e796c92553c658300a4882dde961a0678a}
     version: 45.0.0
     engines: {node: '>=22.0.0'}
 
@@ -4946,8 +4946,8 @@ packages:
     resolution: {integrity: sha512-LaNjtRWUBY++zB5nE/NwcaoMylSPk+S+ZHNB1TzdbMJMny6dynpAGt7X/tl/QYq3TIeE6nxHppbo2LGymrG5Pw==}
     engines: {node: '>=10'}
 
-  p-retry@8.0.1:
-    resolution: {integrity: sha512-NAigyu8hfvJe7MsS18mnc4is0MZtau3QMdBklaJKK23oBQb6occO3UPM3vHmTckW8KhfyjMZaUOqdTFEYliHgg==}
+  p-retry@9.0.0:
+    resolution: {integrity: sha512-HuEats8gYn/UUYa5uyveyQGv75mQmwdFtuMgnZlS12dj/7bdnJSO6keaTjgcZUhvkANTj5EO3lACUmV3xmgj0Q==}
     engines: {node: '>=22'}
 
   p-try@2.2.0:
@@ -5318,6 +5318,10 @@ packages:
   randomfill@1.0.4:
     resolution: {integrity: sha512-87lcbR8+MhcWcUiQ+9e+Rwx8MyR2P7qnt15ynUlbm3TU/fjbgz4GsvfSUDTemtCCtVCqb4ZcEFlyPNTh9bBTLw==}
 
+  re2js@2.9.1:
+    resolution: {integrity: sha512-JIT3bEEUZTOR2YS1walNEIfH4cF/cQeZcBUFq7ldqO6lR6g0X5CBq/S8rsa9omzZcsNf8qc36jCkWpKKtncrZg==}
+    engines: {node: '>=20.0.0'}
+
   react-docgen-typescript@2.4.0:
     resolution: {integrity: sha512-ZtAp5XTO5HRzQctjPU0ybY0RRCQO19X/8fxn3w7y2VVTUbGHDKULPTL4ky3vB05euSgG5NpALhEhDPvQ56wvXg==}
     peerDependencies:
@@ -10409,7 +10413,7 @@ snapshots:
 
   matrix-events-sdk@0.0.1: {}
 
-  matrix-js-sdk@https://codeload.github.com/matrix-org/matrix-js-sdk/tar.gz/a9ef09fbf2f1644c8663d0aeaf6a921cd16e7b01:
+  matrix-js-sdk@https://codeload.github.com/matrix-org/matrix-js-sdk/tar.gz/dc8610e796c92553c658300a4882dde961a0678a:
     dependencies:
       '@babel/runtime': 8.0.8
       '@matrix-org/matrix-sdk-crypto-wasm': 18.9.0
@@ -10419,7 +10423,8 @@ snapshots:
       loglevel: 1.9.2
       matrix-events-sdk: 0.0.1
       matrix-widget-api: 1.20.0
-      p-retry: 8.0.1
+      p-retry: 9.0.0
+      re2js: 2.9.1
       sdp-transform: 3.0.0
       unhomoglyph: 1.0.6
 
@@ -10741,7 +10746,7 @@ snapshots:
     dependencies:
       p-limit: 3.1.0
 
-  p-retry@8.0.1:
+  p-retry@9.0.0:
     dependencies:
       is-network-error: 1.3.2
 
@@ -11165,6 +11170,8 @@ snapshots:
       randombytes: 2.1.0
       safe-buffer: 5.2.1
 
+  re2js@2.9.1: {}
+
   react-docgen-typescript@2.4.0(typescript@5.9.3):
     dependencies:
       typescript: 5.9.3

sdk-target-based-on-call-view-model/main.ts

@@ -132,16 +132,16 @@ export async function createMatrixRTCSdk(
         room,
         mediaDevices,
         muteStates,
-        encryptionSystem,
-        // The bundle owns its page, so the body is the space it has
-        scope.behavior(observeElementSize$(document.body)),
-        of({}),
-        of({}),
         {
           ...callViewModelOptionsFromParams(urlParams),
+          encryptionSystem,
           capture,
           hostBridge,
+          // The bundle owns its page, so the body is the space it has
+          windowSize$: scope.behavior(observeElementSize$(document.body)),
         },
+        of({}),
+        of({}),
       );
       // Once the hang-up has gone through, unstick and ask the host to close us
       vm.leave$

sdk/src/LocalMedia.test.ts

@@ -162,6 +162,7 @@ describe("createLocalMedia", () => {
     media.release("camera");
     expect(trackBehind(camera).stop).toHaveBeenCalled();
     expect(media.tracks$.value).toEqual([microphone]);
+    expect(media.requests.map((r) => r.source)).toEqual(["microphone"]);
 
     media.stop();
     expect(trackBehind(microphone).stop).toHaveBeenCalled();

sdk/src/LocalMedia.ts

@@ -107,6 +107,7 @@ export function createLocalMedia(
     if (source !== "microphone" && source !== "camera") return;
     capturedTracks.get(source)?.stop();
     capturedTracks.delete(source);
+    requests.delete(source);
     publishCapturedTracks();
   };
 

sdk/src/RTCParticipation.ts

@@ -184,6 +184,7 @@ export function createRTCParticipation(
           encryptMedia: encryptionSystem.kind !== E2eeType.NONE,
           matrixRTCMode,
           sendNotificationType: options.sendNotificationType,
+          callIntent: options.callIntent,
           applicationData: options.applicationData,
           timings,
           delayedLeave,

sdk/src/api.ts

@@ -12,6 +12,7 @@ Please see LICENSE in the repository root for full details.
  */
 
 import {
+  type RTCCallIntent,
   type RTCNotificationType,
   type Transport,
 } from "matrix-js-sdk/lib/matrixrtc";
@@ -103,11 +104,14 @@ export interface RTCParticipationOptions {
    * to a notification (ringing, timeouts, declines) is the application's job.
    */
   sendNotificationType?: RTCNotificationType;
+  /**
+   * The kind of call the local member intends to take part in: `"m.audio"`
+   * or `"m.video"`. Carried by the membership as a field of its own.
+   */
+  callIntent?: RTCCallIntent;
   /**
    * Whatever the application wants to say about itself in the membership,
-   * under namespaced keys. Opaque to the SDK, apart from `m.call.intent`
-   * (`"audio"` or `"video"`), which the membership format carries as a
-   * field of its own.
+   * under namespaced keys. Opaque to the SDK.
    */
   applicationData?: Record<string, unknown>;
   /** Timings the host has configured; the defaults otherwise. */
@@ -287,7 +291,7 @@ export interface RTCMember {
   memberId: string;
   /** Which transport this member is on; undefined when the membership has none. */
   transport$: Behavior<TransportMetadata | undefined>;
-  /** What the member's application says about itself, e.g. `m.call.intent`. */
+  /** What the member's application says about itself, e.g. `intent`. */
   applicationData$: Behavior<Record<string, unknown>>;
 
   displayName$: Behavior<string>;

sdk/src/matrixrtc/joinJsSdkSession.test.ts

@@ -60,7 +60,7 @@ describe("joinJsSdkSession", () => {
     expect(s.join).toHaveBeenCalledWith(ownMemberMock, [transportWithAlias], {
       notificationType: "ring",
       callIntent: undefined,
-      applicationData: {},
+      applicationData: undefined,
       manageMediaKeys: true,
       delayedLeaveEventRestartMs: 300_000,
       delayedLeaveEventDelayMs: 3_600_000,
@@ -95,13 +95,14 @@ describe("joinJsSdkSession", () => {
     );
   });
 
-  it("lifts the call intent out of the application data and sends sticky events in Matrix 2.0 mode", () => {
+  it("passes the call intent and application data through and sends sticky events in Matrix 2.0 mode", () => {
     const s = session();
 
     joinJsSdkSession("!room:example.org", s, ownMemberMock, transport, {
       encryptMedia: true,
       matrixRTCMode: MatrixRTCMode.Matrix_2_0,
-      applicationData: { "m.call.intent": "audio", custom: 1 },
+      callIntent: "m.audio",
+      applicationData: { custom: 1 },
       timings: defaultSessionTimings,
       delayedLeave: defaultSessionTimings.delayedLeave,
     });
@@ -110,7 +111,7 @@ describe("joinJsSdkSession", () => {
       ownMemberMock,
       [transportWithAlias],
       expect.objectContaining({
-        callIntent: "audio",
+        callIntent: "m.audio",
         applicationData: { custom: 1 },
         unstableSendStickyEvents: true,
       }),
@@ -124,7 +125,8 @@ describe("joinJsSdkSession", () => {
     joinJsSdkSession("!room:example.org", s, ownMemberMock, transport, {
       encryptMedia: true,
       matrixRTCMode: MatrixRTCMode.Matrix_2_0,
-      applicationData: { "m.call.intent": "audio", custom: 1 },
+      callIntent: "m.audio",
+      applicationData: { custom: 1 },
       timings: defaultSessionTimings,
       delayedLeave: defaultSessionTimings.delayedLeave,
     });
@@ -133,7 +135,7 @@ describe("joinJsSdkSession", () => {
       ownMemberMock,
       [transport],
       expect.objectContaining({
-        callIntent: "audio",
+        callIntent: "m.audio",
         applicationData: { custom: 1 },
         unstableSendStickyEvents: true,
       }),

sdk/src/matrixrtc/joinJsSdkSession.ts

@@ -23,6 +23,7 @@ interface Options {
   encryptMedia: boolean;
   matrixRTCMode: MatrixRTCMode;
   sendNotificationType?: RTCNotificationType;
+  callIntent?: RTCCallIntent;
   applicationData?: Record<string, unknown>;
   timings: SessionTimings;
   /** The delayed leave timings to use: delegated to the SFU or not. */
@@ -43,15 +44,12 @@ export function joinJsSdkSession(
     encryptMedia,
     matrixRTCMode,
     sendNotificationType,
+    callIntent,
     applicationData,
     timings,
     delayedLeave,
   }: Options,
 ): void {
-  // The membership format carries the intent as a field of its own
-  const { "m.call.intent": intent, ...rest } = applicationData ?? {};
-  const callIntent =
-    typeof intent === "string" ? (intent as RTCCallIntent) : undefined;
   // Give up on the network as soon as either the sync has been down for the
   // grace period or the delayed leave has probably been sent, whichever is
   // sooner
@@ -78,7 +76,7 @@ export function joinJsSdkSession(
     {
       notificationType: sendNotificationType,
       callIntent,
-      applicationData: rest,
+      applicationData,
       manageMediaKeys: encryptMedia,
       delayedLeaveEventRestartMs: delayedLeave.restart_ms,
       delayedLeaveEventDelayMs: delayedLeave.delay_ms,

src/App.tsx

@@ -23,14 +23,13 @@ import {
 import * as Sentry from "@sentry/react";
 import { TooltipProvider } from "@vector-im/compound-web";
 import { logger } from "matrix-js-sdk/lib/logger";
-import { type MatrixClient } from "matrix-js-sdk";
 import { I18nextProvider } from "react-i18next";
 
 import { HomePage } from "./home/HomePage";
 import { LoginPage } from "./auth/LoginPage";
 import { RegisterPage } from "./auth/RegisterPage";
 import { RoomPage } from "./room/RoomPage";
-import { ClientProvider } from "./ClientContext";
+import { ClientManagerProvider, ClientProvider } from "./ClientContext";
 import { ErrorPage, LoadingPage } from "./FullScreenView";
 import { Initializer } from "./initializer";
 import { type WidgetHelpers } from "./widget";
@@ -131,22 +130,9 @@ export const App: FC<Props> = ({ vm, widget }) => {
       .catch(logger.error);
   });
 
-  // As a widget, the client comes from the host over the widget API. Standalone,
-  // Element Call finds one itself, so there is nothing to wait for here.
-  const [widgetClient, setWidgetClient] = useState<MatrixClient | undefined>(
-    undefined,
-  );
-  useEffect(() => {
-    if (widget === null) return;
-    widget.client
-      .then(setWidgetClient)
-      .catch((e) => logger.error("Failed to obtain the host's client", e));
-  }, [widget]);
-  const clientReady = widget === null || widgetClient !== undefined;
-
-  const content =
-    loaded && clientReady ? (
-      <ClientProvider client={widgetClient}>
+  const content = loaded ? (
+    <ClientProvider session={vm.clientSession}>
+      <ClientManagerProvider value={vm.clientManager}>
         <MediaDevicesContext value={vm.mediaDevices}>
           <BackgroundEffectsProvider effects={vm.backgroundEffects}>
             <Sentry.ErrorBoundary
@@ -161,10 +147,11 @@ export const App: FC<Props> = ({ vm, widget }) => {
             </Sentry.ErrorBoundary>
           </BackgroundEffectsProvider>
         </MediaDevicesContext>
-      </ClientProvider>
-    ) : (
-      <LoadingPage />
-    );
+      </ClientManagerProvider>
+    </ClientProvider>
+  ) : (
+    <LoadingPage />
+  );
 
   return (
     <I18nextProvider i18n={i18n}>

src/Avatar.test.tsx

@@ -12,6 +12,7 @@ import { type FC, type PropsWithChildren } from "react";
 
 import { ClientContextProvider } from "./ClientContext";
 import { Avatar } from "./Avatar";
+import { hostClientSession } from "./state/ClientSession";
 import { mockMatrixRoomMember, mockRtcMembership } from "./utils/test";
 import {
   type HostBridge,
@@ -26,22 +27,7 @@ const TestComponent: FC<
   }>
 > = ({ client, hostBridge = nullHostBridge, children }) => {
   return (
-    <ClientContextProvider
-      value={{
-        state: "valid",
-        disconnected: false,
-        supportedFeatures: {
-          reactions: true,
-        },
-        setClient: vi.fn(),
-        authenticated: {
-          client,
-          isPasswordlessUser: true,
-          changePassword: vi.fn(),
-          logout: vi.fn(),
-        },
-      }}
-    >
+    <ClientContextProvider value={hostClientSession(client)}>
       <HostBridgeProvider value={hostBridge}>{children}</HostBridgeProvider>
     </ClientContextProvider>
   );

src/Avatar.tsx

@@ -15,7 +15,7 @@ import {
 import { Avatar as CompoundAvatar } from "@vector-im/compound-web";
 import { type MatrixClient } from "matrix-js-sdk";
 
-import { useClientState } from "./ClientContext";
+import { useClient } from "./ClientContext";
 import { useHostBridge } from "./HostBridge";
 
 export enum Size {
@@ -74,7 +74,7 @@ export const Avatar: FC<Props> = ({
   style,
   ...props
 }) => {
-  const clientState = useClientState();
+  const { client } = useClient();
   const hostBridge = useHostBridge();
 
   const sizePx = useMemo(
@@ -87,7 +87,7 @@ export const Avatar: FC<Props> = ({
 
   const [avatarUrl, setAvatarUrl] = useState<string | undefined>(undefined);
 
-  // In theory, a change in `clientState` or `sizePx` could run extra media
+  // In theory, a change in `client` or `sizePx` could run extra media
   // downloads, but in practice they should be stable long before this code runs.
   useEffect(() => {
     if (!src) {
@@ -99,12 +99,8 @@ export const Avatar: FC<Props> = ({
 
     if (hostBridge.downloadMedia) {
       blob = hostBridge.downloadMedia(src);
-    } else if (
-      clientState?.state === "valid" &&
-      clientState.authenticated?.client &&
-      sizePx
-    ) {
-      blob = getAvatarFromServer(clientState.authenticated.client, src, sizePx);
+    } else if (client && sizePx) {
+      blob = getAvatarFromServer(client, src, sizePx);
     } else {
       setAvatarUrl(undefined);
       return;
@@ -133,7 +129,7 @@ export const Avatar: FC<Props> = ({
         URL.revokeObjectURL(objectUrl);
       }
     };
-  }, [clientState, hostBridge, src, sizePx]);
+  }, [client, hostBridge, src, sizePx]);
 
   return (
     <CompoundAvatar

src/ClientContext.test.tsx

@@ -6,12 +6,25 @@ Please see LICENSE in the repository root for full details.
 */
 
 import { expect, test, vi } from "vitest";
-import { render, waitFor } from "@testing-library/react";
+import { act, render, renderHook } from "@testing-library/react";
 import { BrowserRouter } from "react-router-dom";
 import { type MatrixClient } from "matrix-js-sdk";
 import { type FC } from "react";
+import { BehaviorSubject } from "rxjs";
 
-import { ClientProvider, useClientState } from "./ClientContext";
+import {
+  ClientManagerProvider,
+  ClientProvider,
+  useClientManager,
+  useClientManagerIfAny,
+  useClientSessionState,
+} from "./ClientContext";
+import {
+  type ClientManager,
+  type ClientSession,
+  type ClientSessionState,
+  hostClientSession,
+} from "./state/ClientSession";
 
 const mockClient = (userId = "@alice:example.org"): MatrixClient =>
   ({
@@ -24,67 +37,47 @@ const mockClient = (userId = "@alice:example.org"): MatrixClient =>
 
 /** Reports what the context says, so a test can assert on it. */
 const ShowClientState: FC = () => {
-  const state = useClientState();
-  if (state === undefined) return <span>loading</span>;
-  if (state.state === "error") return <span>error</span>;
-  return (
-    <span>{state.authenticated?.client.getUserId() ?? "unauthenticated"}</span>
-  );
+  const state = useClientSessionState();
+  switch (state.state) {
+    case "signedIn":
+      return <span>{state.client.getUserId()}</span>;
+    case "signedOut":
+      return <span>unauthenticated</span>;
+    default:
+      return <span>{state.state}</span>;
+  }
 };
 
-test("uses a client supplied by the host without waiting", () => {
-  const client = mockClient();
-
-  const { container } = render(
+const renderProvider = (
+  session: ClientSession,
+  children = <ShowClientState />,
+): ReturnType<typeof render> =>
+  render(
     <BrowserRouter>
-      <ClientProvider client={client}>
-        <ShowClientState />
-      </ClientProvider>
+      <ClientProvider session={session}>{children}</ClientProvider>
     </BrowserRouter>,
   );
 
+test("uses a client supplied by the host without waiting", () => {
+  const { container } = renderProvider(hostClientSession(mockClient()));
+
   // Available on the very first render: a supplied client needs no session
   // restoring, so there is no loading state to pass through.
   expect(container.textContent).toBe("@alice:example.org");
 });
 
-test("does not claim exclusive use of storage when given a client", () => {
-  // The channel is created when the module loads, so spy on the prototype
-  // rather than trying to replace the global.
-  const postMessage = vi.spyOn(BroadcastChannel.prototype, "postMessage");
-
-  render(
-    <BrowserRouter>
-      <ClientProvider client={mockClient()}>
-        <ShowClientState />
-      </ClientProvider>
-    </BrowserRouter>,
-  );
-
-  // The broadcast shuts down other instances to protect Element Call's own
-  // stores. A host's client brings its own, so there is nothing to protect.
-  expect(postMessage).not.toHaveBeenCalled();
-
-  postMessage.mockRestore();
-});
-
 test("follows the client when the host swaps it", () => {
-  const first = mockClient();
-  const second = mockClient("@bob:example.org");
-
-  const { container, rerender } = render(
-    <BrowserRouter>
-      <ClientProvider client={first}>
-        <ShowClientState />
-      </ClientProvider>
-    </BrowserRouter>,
+  const { container, rerender } = renderProvider(
+    hostClientSession(mockClient()),
   );
   expect(container.textContent).toBe("@alice:example.org");
 
   // A host that re-authenticates hands us a new client on a mounted component
   rerender(
     <BrowserRouter>
-      <ClientProvider client={second}>
+      <ClientProvider
+        session={hostClientSession(mockClient("@bob:example.org"))}
+      >
         <ShowClientState />
       </ClientProvider>
     </BrowserRouter>,
@@ -93,23 +86,63 @@ test("follows the client when the host swaps it", () => {
   expect(container.textContent).toBe("@bob:example.org");
 });
 
-test("finds a client of its own when the host supplies none", async () => {
-  const client = mockClient();
-  vi.doMock("./utils/spa", () => ({
-    initSPA: vi.fn().mockResolvedValue({ client, passwordlessUser: true }),
-  }));
-
-  const { container } = render(
-    <BrowserRouter>
-      <ClientProvider>
-        <ShowClientState />
-      </ClientProvider>
-    </BrowserRouter>,
-  );
+test("follows a session of its own as it is restored", () => {
+  const state$ = new BehaviorSubject<ClientSessionState>({ state: "loading" });
+  const { container } = renderProvider({ state$ });
 
   // Nothing to show until a session has been restored or created
   expect(container.textContent).toBe("loading");
-  await waitFor(() => expect(container.textContent).toBe("@alice:example.org"));
+  act(() =>
+    state$.next({
+      state: "signedIn",
+      client: mockClient(),
+      passwordlessUser: true,
+    }),
+  );
+  expect(container.textContent).toBe("@alice:example.org");
+});
 
-  vi.doUnmock("./utils/spa");
+test("has no one signed in when the session says so", () => {
+  const { container } = renderProvider({
+    state$: new BehaviorSubject<ClientSessionState>({ state: "signedOut" }),
+  });
+  expect(container.textContent).toBe("unauthenticated");
+});
+
+test("shows the session's error in place of its children", () => {
+  const { container } = renderProvider({
+    state$: new BehaviorSubject<ClientSessionState>({
+      state: "error",
+      error: new Error("Opened elsewhere"),
+    }),
+  });
+  // The error page, not the children
+  expect(container.textContent).not.toContain("error");
+  expect(container.textContent).toContain("Something went wrong");
+});
+
+test("hands the session's manager to views that need one", () => {
+  const manager: ClientManager = {
+    login: vi.fn(),
+    register: vi.fn(),
+    logout: vi.fn(),
+  };
+  const { result } = renderHook(
+    () => [useClientManager(), useClientManagerIfAny()],
+    {
+      wrapper: ({ children }) => (
+        <ClientManagerProvider value={manager}>
+          <>{children}</>
+        </ClientManagerProvider>
+      ),
+    },
+  );
+  expect(result.current).toEqual([manager, manager]);
+});
+
+test("has no manager for a host's session", () => {
+  // The component and the widget provide none; a view that insists on one is
+  // in the wrong build
+  expect(renderHook(() => useClientManagerIfAny()).result.current).toBeNull();
+  expect(() => renderHook(() => useClientManager())).toThrow();
 });

src/ClientContext.tsx

@@ -5,30 +5,18 @@ SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
 Please see LICENSE in the repository root for full details.
 */
 
-import {
-  type FC,
-  useCallback,
-  useEffect,
-  useState,
-  createContext,
-  use,
-  useRef,
-  useMemo,
-  type JSX,
-} from "react";
-import { logger } from "matrix-js-sdk/lib/logger";
-import { type ISyncStateData, type SyncState } from "matrix-js-sdk/lib/sync";
-import { ClientEvent, type MatrixClient } from "matrix-js-sdk";
+import { type FC, useEffect, createContext, use, type JSX } from "react";
+import { type MatrixClient } from "matrix-js-sdk";
 
 import { ErrorPage } from "./FullScreenView";
-import { useHostBridge } from "./HostBridge";
-import { useLeaveToHome } from "./LeaveToHomeContext";
+import { PosthogAnalytics } from "./analytics/PosthogAnalytics";
+import { useBehavior } from "./useBehavior";
+import { constant } from "./state/Behavior";
 import {
-  PosthogAnalytics,
-  RegistrationType,
-} from "./analytics/PosthogAnalytics";
-import { useEventTarget } from "./useEvents";
-import { OpenElsewhereError } from "./RichError";
+  type ClientManager,
+  type ClientSession,
+  type ClientSessionState,
+} from "./state/ClientSession";
 
 declare global {
   interface Window {
@@ -37,360 +25,70 @@ declare global {
   }
 }
 
-export type ClientState = ValidClientState | ErrorState;
-
-export type ValidClientState = {
-  state: "valid";
-  authenticated?: AuthenticatedClient;
-  // 'Disconnected' rather than 'connected' because it tracks specifically
-  // whether the client is supposed to be connected but is not
-  disconnected: boolean;
-  supportedFeatures: {
-    reactions: boolean;
-  };
-  setClient: (client: MatrixClient, session: Session) => void;
+// Without a provider, no one is signed in and there is no session to act on
+const noClientSession: ClientSession = {
+  state$: constant({ state: "signedOut" }),
 };
 
-export type AuthenticatedClient = {
-  client: MatrixClient;
-  isPasswordlessUser: boolean;
-  changePassword: (password: string) => Promise<void>;
-  logout: () => void;
-};
-
-export type ErrorState = {
-  state: "error";
-  error: Error;
-};
-
-const ClientContext = createContext<ClientState | undefined>(undefined);
+const ClientContext = createContext<ClientSession>(noClientSession);
 
 export const ClientContextProvider = ClientContext.Provider;
 
-export const useClientState = (): ClientState | undefined => use(ClientContext);
+export const useClientSessionState = (): ClientSessionState =>
+  useBehavior(use(ClientContext).state$);
 
-export function useClient(): {
-  client?: MatrixClient;
-  setClient?: (client: MatrixClient, session: Session) => void;
-} {
-  let client;
-  let setClient;
-
-  const clientState = useClientState();
-  if (clientState?.state === "valid") {
-    client = clientState.authenticated?.client;
-    setClient = clientState.setClient;
-  }
-
-  return { client, setClient };
+export function useClient(): { client?: MatrixClient } {
+  const state = useClientSessionState();
+  return { client: state.state === "signedIn" ? state.client : undefined };
 }
 
-// Plain representation of the `ClientContext` as a helper for old components that expected an object with multiple fields.
-export function useClientLegacy(): {
-  client?: MatrixClient;
-  setClient?: (client: MatrixClient, session: Session) => void;
-  passwordlessUser: boolean;
-  loading: boolean;
-  authenticated: boolean;
-  logout?: () => void;
-  error?: Error;
-} {
-  const clientState = useClientState();
+// Null where the session is a host's: the component, and the widget
+const ClientManagerContext = createContext<ClientManager | null>(null);
 
-  let client;
-  let setClient;
-  let passwordlessUser = false;
-  let loading = true;
-  let error;
-  let authenticated = false;
-  let logout;
+export const ClientManagerProvider = ClientManagerContext.Provider;
 
-  if (clientState?.state === "valid") {
-    client = clientState.authenticated?.client;
-    setClient = clientState.setClient;
-    passwordlessUser = clientState.authenticated?.isPasswordlessUser ?? false;
-    loading = false;
-    authenticated = client !== undefined;
-    logout = clientState.authenticated?.logout;
-  } else if (clientState?.state === "error") {
-    error = clientState.error;
-    loading = false;
-  }
-
-  return {
-    client,
-    setClient,
-    passwordlessUser,
-    loading,
-    authenticated,
-    logout,
-    error,
-  };
+/**
+ * The manager of a session that is Element Call's own, for views that only
+ * the standalone app mounts: the login and registration pages. Throws
+ * elsewhere, as those views have no business being there.
+ */
+export function useClientManager(): ClientManager {
+  const manager = use(ClientManagerContext);
+  if (manager === null)
+    throw new Error("This view needs a session of Element Call's own");
+  return manager;
 }
 
-const loadChannel =
-  "BroadcastChannel" in window ? new BroadcastChannel("load") : null;
+/**
+ * The session's manager, or null where the session is a host's. For views
+ * shared with the widget, which can offer to sign out only when that is ours
+ * to do.
+ */
+export const useClientManagerIfAny = (): ClientManager | null =>
+  use(ClientManagerContext);
 
 interface Props {
   children: JSX.Element;
-  /**
-   * The client Element Call should use.
-   *
-   * An application hosting Element Call as a component already has a client,
-   * and owns the user's session; supplying it here means Element Call neither
-   * authenticates anyone nor manages their session. Left out, Element Call finds a client
-   * itself — from the widget API, or by restoring or creating a session of its
-   * own.
-   */
-  client?: MatrixClient;
+  /** a session from Element Call SPA, from a widget or the host (EW) */
+  session: ClientSession;
 }
 
-export const ClientProvider: FC<Props> = ({ children, client }) => {
-  const leaveToHome = useLeaveToHome();
-  const hostBridge = useHostBridge();
-
-  // null = signed out, undefined = loading
-  const [initClientState, setInitClientState] = useState<
-    InitResult | null | undefined
-  >(
-    client === undefined
-      ? undefined
-      : // A supplied client belongs to the host, so there is no session of ours
-        // to restore and nothing to wait for.
-        { client, passwordlessUser: false },
-  );
-
-  const initializing = useRef(false);
-  useEffect(() => {
-    if (client !== undefined) {
-      // Nothing to load, but a host may hand us a different client later — on
-      // re-authenticating, say — so follow whichever one it has given us.
-      setInitClientState((current) =>
-        current?.client === client
-          ? current
-          : { client, passwordlessUser: false },
-      );
-      // Analytics still need to follow the user's choices.
-      if (PosthogAnalytics.instance.isEnabled())
-        PosthogAnalytics.instance.startListeningToSettingsChanges();
-      return;
-    }
-    // In case the component is mounted, unmounted, and remounted quickly (as
-    // React does in strict mode), we need to make sure not to doubly initialize
-    // the client.
-    if (initializing.current) return;
-    initializing.current = true;
-
-    loadClient()
-      .then((initResult) => {
-        setInitClientState(initResult);
-        if (PosthogAnalytics.instance.isEnabled())
-          PosthogAnalytics.instance.startListeningToSettingsChanges();
-      })
-      .catch((err) => logger.error(err))
-      .finally(() => (initializing.current = false));
-  }, [client]);
-
-  const changePassword = useCallback(
-    async (password: string) => {
-      const session = loadSession();
-      if (!initClientState?.client || !session) {
-        return;
-      }
-
-      await initClientState.client.setPassword(
-        {
-          type: "m.login.password",
-          identifier: {
-            type: "m.id.user",
-            user: session.user_id,
-          },
-          user: session.user_id,
-          password: session.tempPassword,
-        },
-        password,
-      );
-
-      saveSession({ ...session, passwordlessUser: false });
-
-      setInitClientState({
-        ...initClientState,
-        passwordlessUser: false,
-      });
-    },
-    [initClientState],
-  );
-
-  const setClient = useCallback(
-    (client: MatrixClient, session: Session) => {
-      const oldClient = initClientState?.client;
-      if (oldClient && oldClient !== client) {
-        oldClient.stopClient();
-      }
-
-      saveSession(session);
-      setInitClientState({
-        client,
-        passwordlessUser: session.passwordlessUser,
-      });
-      if (PosthogAnalytics.instance.isEnabled())
-        PosthogAnalytics.instance.startListeningToSettingsChanges();
-    },
-    [initClientState?.client],
-  );
-
-  const logout = useCallback(async () => {
-    const client = initClientState?.client;
-    if (!client) {
-      return;
-    }
-
-    await client.logout(true);
-    await client.clearStores();
-    clearSession();
-    setInitClientState(null);
-    leaveToHome?.();
-    PosthogAnalytics.instance.logout();
-    PosthogAnalytics.instance.setRegistrationType(RegistrationType.Guest);
-  }, [leaveToHome, initClientState?.client]);
-
-  // To protect against multiple sessions writing to the same storage
-  // simultaneously, we send a broadcast message that shuts down all other
-  // running instances of the app. Element Call only has storage of its own to
-  // protect when it created the session itself; given a client — by a host, or
-  // over the widget API — it is mostly stateless.
-  const ownsSession = client === undefined;
-  useEffect(() => {
-    if (ownsSession) loadChannel?.postMessage({});
-  }, [ownsSession]);
-
-  const [alreadyOpenedErr, setAlreadyOpenedErr] = useState<Error | undefined>(
-    undefined,
-  );
-  useEventTarget(
-    loadChannel,
-    "message",
-    useCallback(() => {
-      initClientState?.client.stopClient();
-      setAlreadyOpenedErr(new OpenElsewhereError());
-    }, [initClientState?.client, setAlreadyOpenedErr]),
-  );
-
-  const [isDisconnected, setIsDisconnected] = useState(false);
-  const [supportsReactions, setSupportsReactions] = useState(false);
-
-  const state: ClientState | undefined = useMemo(() => {
-    if (alreadyOpenedErr) {
-      return { state: "error", error: alreadyOpenedErr };
-    }
-
-    if (initClientState === undefined) return undefined;
-
-    const authenticated =
-      initClientState === null
-        ? undefined
-        : {
-            client: initClientState.client,
-            isPasswordlessUser: initClientState.passwordlessUser,
-            changePassword,
-            logout,
-          };
-
-    return {
-      state: "valid",
-      authenticated,
-      setClient,
-      disconnected: isDisconnected,
-      supportedFeatures: {
-        reactions: supportsReactions,
-      },
-    };
-  }, [
-    alreadyOpenedErr,
-    changePassword,
-    initClientState,
-    logout,
-    setClient,
-    isDisconnected,
-    supportsReactions,
-  ]);
-
-  const onSync = useCallback(
-    (state: SyncState, _old: SyncState | null, data?: ISyncStateData) => {
-      setIsDisconnected(clientIsDisconnected(state, data));
-    },
-    [],
-  );
+export const ClientProvider: FC<Props> = ({ children, session }) => {
+  const state = useBehavior(session.state$);
 
   useEffect(() => {
-    if (!initClientState) {
-      return;
-    }
-
-    window.matrixclient = initClientState.client;
-    window.passwordlessUser = initClientState.passwordlessUser;
+    if (state.state !== "signedIn") return;
+    window.matrixclient = state.client;
+    window.passwordlessUser = state.passwordlessUser;
 
     if (PosthogAnalytics.hasInstance())
       PosthogAnalytics.instance.onLoginStatusChanged();
+    // Analytics follow the user's choices whoever the client belongs to
+    if (PosthogAnalytics.instance.isEnabled())
+      PosthogAnalytics.instance.startListeningToSettingsChanges();
+  }, [state]);
 
-    if (initClientState.client) {
-      initClientState.client.on(ClientEvent.Sync, onSync);
-    }
+  if (state.state === "error") return <ErrorPage error={state.error} />;
 
-    if (!hostBridge.supportsReactions)
-      logger.warn("The host does not permit reactions");
-    setSupportsReactions(hostBridge.supportsReactions);
-
-    return (): void => {
-      if (initClientState.client) {
-        initClientState.client.removeListener(ClientEvent.Sync, onSync);
-      }
-    };
-  }, [initClientState, onSync, hostBridge]);
-
-  if (alreadyOpenedErr) {
-    return <ErrorPage error={alreadyOpenedErr} />;
-  }
-
-  return <ClientContext value={state}>{children}</ClientContext>;
+  return <ClientContext value={session}>{children}</ClientContext>;
 };
-
-export type InitResult = {
-  client: MatrixClient;
-  passwordlessUser: boolean;
-};
-
-/**
- * Restores or creates a session of Element Call's own. Only reached when no
- * client was supplied for it to use.
- */
-async function loadClient(): Promise<InitResult | null> {
-  const { initSPA } = await import("./utils/spa");
-  return initSPA(loadSession, clearSession);
-}
-
-export interface Session {
-  user_id: string;
-  device_id: string;
-  access_token: string;
-  passwordlessUser: boolean;
-  tempPassword?: string;
-}
-
-const clearSession = (): void => localStorage.removeItem("matrix-auth-store");
-const saveSession = (s: Session): void =>
-  localStorage.setItem("matrix-auth-store", JSON.stringify(s));
-const loadSession = (): Session | undefined => {
-  const data = localStorage.getItem("matrix-auth-store");
-  if (!data) {
-    return undefined;
-  }
-
-  return JSON.parse(data);
-};
-
-const clientIsDisconnected = (
-  syncState: SyncState,
-  syncData?: ISyncStateData,
-): boolean =>
-  syncState === "ERROR" && syncData?.error?.name === "ConnectionError";

src/DisconnectedBanner.test.tsx

@@ -0,0 +1,43 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { expect, test, vi } from "vitest";
+import { act, render } from "@testing-library/react";
+import { type MatrixClient } from "matrix-js-sdk";
+
+import { ClientProvider } from "./ClientContext";
+import { DisconnectedBanner } from "./DisconnectedBanner";
+import { hostClientSession } from "./state/ClientSession";
+
+test("shows while the client's sync fails to connect", () => {
+  const client = {
+    on: vi.fn(),
+    removeListener: vi.fn(),
+    getUserId: () => "@alice:example.org",
+  } as Partial<MatrixClient> as MatrixClient;
+  const { container } = render(
+    <ClientProvider session={hostClientSession(client)}>
+      <DisconnectedBanner />
+    </ClientProvider>,
+  );
+  expect(container.textContent).toBe("");
+
+  const [, onSync] = vi.mocked(client.on).mock.calls[0] as [
+    unknown,
+    (state: string, old: null, data?: { error?: Error }) => void,
+  ];
+  const connectionError = Object.assign(new Error("offline"), {
+    name: "ConnectionError",
+  });
+  act(() => onSync("ERROR", null, { error: connectionError }));
+  expect(container.textContent).not.toBe("");
+  // Any other failure is not a connection problem
+  act(() => onSync("ERROR", null, { error: new Error("rate limited") }));
+  expect(container.textContent).toBe("");
+  act(() => onSync("SYNCING", null));
+  expect(container.textContent).toBe("");
+});

src/DisconnectedBanner.tsx

@@ -6,30 +6,60 @@ Please see LICENSE in the repository root for full details.
 */
 
 import classNames from "classnames";
-import { type FC, type HTMLAttributes, type ReactNode } from "react";
+import {
+  type FC,
+  type HTMLAttributes,
+  type ReactNode,
+  useEffect,
+  useState,
+} from "react";
 import { useTranslation } from "react-i18next";
+import { ClientEvent, type MatrixClient } from "matrix-js-sdk";
+import { type ISyncStateData, type SyncState } from "matrix-js-sdk/lib/sync";
 
 import styles from "./DisconnectedBanner.module.css";
-import { type ValidClientState, useClientState } from "./ClientContext";
+import { useClient } from "./ClientContext";
 
 interface Props extends HTMLAttributes<HTMLElement> {
   children?: ReactNode;
   className?: string;
 }
 
+/**
+ * Shown while the signed-in client is supposed to be connected but is not.
+ */
 export const DisconnectedBanner: FC<Props> = ({
   children,
   className,
   ...rest
 }) => {
   const { t } = useTranslation();
-  const clientState = useClientState();
-  let shouldShowBanner = false;
+  const { client } = useClient();
+  // Tagged with the client it describes, so that a swapped client does not
+  // inherit the old one's verdict before its first sync
+  const [disconnected, setDisconnected] = useState<
+    [MatrixClient, boolean] | null
+  >(null);
 
-  if (clientState?.state === "valid") {
-    const validClientState = clientState as ValidClientState;
-    shouldShowBanner = validClientState.disconnected;
-  }
+  useEffect(() => {
+    if (client === undefined) return;
+    const onSync = (
+      syncState: SyncState,
+      _old: SyncState | null,
+      data?: ISyncStateData,
+    ): void => {
+      const clientIsDisconnected =
+        syncState === "ERROR" && data?.error?.name === "ConnectionError";
+      setDisconnected([client, clientIsDisconnected]);
+    };
+    client.on(ClientEvent.Sync, onSync);
+    return (): void => {
+      client.removeListener(ClientEvent.Sync, onSync);
+    };
+  }, [client]);
+
+  const shouldShowBanner =
+    disconnected !== null && disconnected[0] === client && disconnected[1];
 
   return (
     <>

src/UrlConfiguration.ts

@@ -18,6 +18,8 @@ Please see LICENSE in the repository root for full details.
  */
 
 import {
+  RTC_CALL_INTENT_AUDIO,
+  RTC_CALL_INTENT_VIDEO,
   type RTCCallIntent,
   type RTCNotificationType,
 } from "matrix-js-sdk/lib/matrixrtc";
@@ -179,40 +181,40 @@ export function configurationForIntent(intent: UserIntent): UrlConfiguration {
   switch (intent) {
     case UserIntent.StartNewCall:
       preset.skipLobby = false;
-      preset.callIntent = "video";
+      preset.callIntent = RTC_CALL_INTENT_VIDEO;
       break;
     case UserIntent.JoinExistingCall:
       // On desktop this will be overridden based on which button was used to join the call
       preset.skipLobby = false;
-      preset.callIntent = "video";
+      preset.callIntent = RTC_CALL_INTENT_VIDEO;
       break;
     case UserIntent.StartNewCallVoice:
       preset.skipLobby = false;
-      preset.callIntent = "audio";
+      preset.callIntent = RTC_CALL_INTENT_AUDIO;
       break;
     case UserIntent.JoinExistingCallVoice:
       // On desktop this will be overridden based on which button was used to join the call
       preset.skipLobby = false;
-      preset.callIntent = "audio";
+      preset.callIntent = RTC_CALL_INTENT_AUDIO;
       break;
     case UserIntent.StartNewCallDMVoice:
-      preset.callIntent = "audio";
+      preset.callIntent = RTC_CALL_INTENT_AUDIO;
     // Fall through
     case UserIntent.StartNewCallDM:
       preset.skipLobby = true;
       preset.sendNotificationType = "ring";
       preset.autoLeaveWhenOthersLeft = true;
       preset.waitForCallPickup = true;
-      preset.callIntent = preset.callIntent ?? "video";
+      preset.callIntent = preset.callIntent ?? RTC_CALL_INTENT_VIDEO;
       break;
     case UserIntent.JoinExistingCallDMVoice:
-      preset.callIntent = "audio";
+      preset.callIntent = RTC_CALL_INTENT_AUDIO;
     // Fall through
     case UserIntent.JoinExistingCallDM:
       // On desktop this will be overridden based on which button was used to join the call
       preset.skipLobby = true;
       preset.autoLeaveWhenOthersLeft = true;
-      preset.callIntent = preset.callIntent ?? "video";
+      preset.callIntent = preset.callIntent ?? RTC_CALL_INTENT_VIDEO;
       break;
     // Non widget usecase defaults
     default:

src/UrlParams.test.ts

@@ -21,6 +21,10 @@ import {
   UserIntent,
 } from "../src/UrlParams";
 import { mockConfig } from "./utils/test";
+import {
+  RTC_CALL_INTENT_AUDIO,
+  RTC_CALL_INTENT_VIDEO,
+} from "matrix-js-sdk/lib/matrixrtc";
 
 const ROOM_NAME = "roomNameHere";
 const ROOM_ID = "!d45f138fsd";
@@ -275,7 +279,7 @@ describe("UrlParams", () => {
       ).toMatchObject({
         ...startNewCallDefaults("desktop"),
         skipLobby: false,
-        callIntent: "video",
+        callIntent: RTC_CALL_INTENT_VIDEO,
       });
     });
 
@@ -322,7 +326,7 @@ describe("UrlParams", () => {
       ).toMatchObject({
         ...startNewCallDefaults("desktop"),
         skipLobby: false,
-        callIntent: "audio",
+        callIntent: RTC_CALL_INTENT_AUDIO,
       });
     });
 
@@ -333,7 +337,7 @@ describe("UrlParams", () => {
         ),
       ).toMatchObject({
         ...joinExistingCallDefaults("desktop"),
-        callIntent: "audio",
+        callIntent: RTC_CALL_INTENT_AUDIO,
       });
     });
 
@@ -348,7 +352,7 @@ describe("UrlParams", () => {
         sendNotificationType: "ring",
         autoLeaveWhenOthersLeft: true,
         waitForCallPickup: true,
-        callIntent: "audio",
+        callIntent: RTC_CALL_INTENT_AUDIO,
       });
     });
 
@@ -363,7 +367,7 @@ describe("UrlParams", () => {
         skipLobby: true,
         autoLeaveWhenOthersLeft: true,
         waitForCallPickup: false,
-        callIntent: "video",
+        callIntent: RTC_CALL_INTENT_VIDEO,
       });
     });
 
@@ -377,7 +381,7 @@ describe("UrlParams", () => {
         skipLobby: true,
         autoLeaveWhenOthersLeft: true,
         waitForCallPickup: false,
-        callIntent: "audio",
+        callIntent: RTC_CALL_INTENT_AUDIO,
       });
     });
   });

src/UserMenuContainer.test.tsx

@@ -0,0 +1,96 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { expect, test, vi } from "vitest";
+import { render, screen } from "@testing-library/react";
+import userEvent from "@testing-library/user-event";
+import { BrowserRouter } from "react-router-dom";
+import { type MatrixClient } from "matrix-js-sdk";
+import { TooltipProvider } from "@vector-im/compound-web";
+import { BehaviorSubject } from "rxjs";
+
+import { ClientManagerProvider, ClientProvider } from "./ClientContext";
+import { LeaveToHomeProvider } from "./LeaveToHomeContext";
+import {
+  type ClientManager,
+  type ClientSession,
+  type ClientSessionState,
+  hostClientSession,
+} from "./state/ClientSession";
+import { UserMenuContainer } from "./UserMenuContainer";
+import { flushPromises } from "./utils/test";
+
+vi.mock("./settings/SettingsModal", () => ({
+  defaultSettingsTab: "audio",
+  SettingsModal: (): null => null,
+}));
+
+const mockClient = (): MatrixClient =>
+  ({
+    on: vi.fn(),
+    removeListener: vi.fn(),
+    getUserId: () => "@alice:example.org",
+    getUserIdLocalpart: () => "alice",
+    getDeviceId: () => "AAAA",
+    getUser: () => null,
+    stopClient: vi.fn(),
+  }) as Partial<MatrixClient> as MatrixClient;
+
+test("leaves for home after logging out of the session", async () => {
+  const logout = vi.fn().mockResolvedValue(undefined);
+  const leaveToHome = vi.fn();
+  renderMenu(
+    {
+      state$: new BehaviorSubject<ClientSessionState>({
+        state: "signedIn",
+        client: mockClient(),
+        passwordlessUser: false,
+      }),
+    },
+    { login: vi.fn(), register: vi.fn(), logout },
+    leaveToHome,
+  );
+
+  await selectSignOut();
+  expect(logout).toHaveBeenCalled();
+  expect(leaveToHome).toHaveBeenCalled();
+});
+
+test("cannot end a session that is not ours", async () => {
+  const leaveToHome = vi.fn();
+  renderMenu(hostClientSession(mockClient()), null, leaveToHome);
+
+  await selectSignOut();
+  expect(leaveToHome).not.toHaveBeenCalled();
+});
+
+async function selectSignOut(): Promise<void> {
+  const user = userEvent.setup();
+  await user.click(screen.getByTestId("usermenu_open"));
+  await user.click(await screen.findByTestId("usermenu_logout"));
+  await flushPromises();
+}
+
+function renderMenu(
+  session: ClientSession,
+  manager: ClientManager | null,
+  leaveToHome: (() => void) | null = null,
+): void {
+  render(
+    <BrowserRouter>
+      <TooltipProvider>
+        <LeaveToHomeProvider value={leaveToHome}>
+          <ClientProvider session={session}>
+            <ClientManagerProvider value={manager}>
+              <UserMenuContainer />
+            </ClientManagerProvider>
+          </ClientProvider>
+        </LeaveToHomeProvider>
+      </TooltipProvider>
+    </BrowserRouter>,
+  );
+}

src/UserMenuContainer.tsx

@@ -9,7 +9,12 @@ import { type FC, useCallback, useState } from "react";
 import { useNavigate, useLocation } from "react-router-dom";
 import { logger } from "matrix-js-sdk/lib/logger";
 
-import { useClientLegacy } from "./ClientContext";
+import {
+  useClient,
+  useClientManagerIfAny,
+  useClientSessionState,
+} from "./ClientContext";
+import { useLeaveToHome } from "./LeaveToHomeContext";
 import { useProfile } from "./profile/useProfile";
 import { defaultSettingsTab, SettingsModal } from "./settings/SettingsModal";
 import { UserMenu } from "./UserMenu";
@@ -21,7 +26,13 @@ interface Props {
 export const UserMenuContainer: FC<Props> = ({ preventNavigation = false }) => {
   const location = useLocation();
   const navigate = useNavigate();
-  const { client, logout, authenticated, passwordlessUser } = useClientLegacy();
+  const { client } = useClient();
+  const session = useClientSessionState();
+  const passwordlessUser =
+    session.state === "signedIn" && session.passwordlessUser;
+  // Absent when the session is a host's, which Element Call cannot end
+  const logout = useClientManagerIfAny()?.logout;
+  const leaveToHome = useLeaveToHome();
   const { displayName, avatarUrl } = useProfile(client);
   const [settingsModalOpen, setSettingsModalOpen] = useState(false);
   const onDismissSettingsModal = useCallback(
@@ -43,7 +54,9 @@ export const UserMenuContainer: FC<Props> = ({ preventNavigation = false }) => {
           setSettingsModalOpen(true);
           break;
         case "logout":
-          logout?.();
+          logout?.()
+            .then(() => leaveToHome?.())
+            .catch((e) => logger.error("Failed to log out", e));
           break;
         case "login":
           navigate("/login", { state: { from: location } })?.catch((error) =>
@@ -52,7 +65,7 @@ export const UserMenuContainer: FC<Props> = ({ preventNavigation = false }) => {
           break;
       }
     },
-    [navigate, location, logout, setSettingsModalOpen],
+    [navigate, location, logout, leaveToHome, setSettingsModalOpen],
   );
 
   const userName = client?.getUserIdLocalpart() ?? "";
@@ -60,7 +73,7 @@ export const UserMenuContainer: FC<Props> = ({ preventNavigation = false }) => {
     <>
       <UserMenu
         preventNavigation={preventNavigation}
-        isAuthenticated={authenticated}
+        isAuthenticated={client !== undefined}
         isPasswordlessUser={passwordlessUser}
         avatarUrl={avatarUrl}
         onAction={onAction}

src/auth/LoginPage.test.tsx

@@ -0,0 +1,78 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { afterEach, beforeEach, expect, test, vi } from "vitest";
+import { render, screen } from "@testing-library/react";
+import userEvent from "@testing-library/user-event";
+import { type FC } from "react";
+import { MemoryRouter, useLocation } from "react-router-dom";
+import { type MatrixClient } from "matrix-js-sdk";
+
+import { LoginPage } from "./LoginPage";
+import { ClientManagerProvider } from "../ClientContext";
+import { type ClientManager } from "../state/ClientSession";
+import { Config } from "../config/Config";
+
+beforeEach(() => {
+  vi.spyOn(Config, "defaultHomeserverUrl").mockReturnValue(
+    "https://hs.example.org",
+  );
+});
+afterEach(() => {
+  vi.restoreAllMocks();
+  vi.clearAllMocks();
+});
+
+test("signs in with the session's manager and goes home", async () => {
+  const manager = mockManager();
+  vi.mocked(manager.login).mockResolvedValue({} as MatrixClient);
+  renderLogin(manager);
+
+  await submit("alice", "hunter2");
+
+  expect(manager.login).toHaveBeenCalledWith(
+    "https://hs.example.org",
+    "alice",
+    "hunter2",
+  );
+  expect(await screen.findByText("at /")).toBeVisible();
+});
+
+test("shows why signing in failed", async () => {
+  const manager = mockManager();
+  vi.mocked(manager.login).mockRejectedValue(new Error("Wrong password"));
+  renderLogin(manager);
+
+  await submit("alice", "hunter2");
+
+  expect(await screen.findByText("Wrong password")).toBeVisible();
+  expect(screen.getByText("at /login")).toBeVisible();
+});
+
+async function submit(username: string, password: string): Promise<void> {
+  const user = userEvent.setup();
+  await user.type(screen.getByTestId("login_username"), username);
+  await user.type(screen.getByTestId("login_password"), password);
+  await user.click(screen.getByTestId("login_login"));
+}
+
+function mockManager(): ClientManager {
+  return { login: vi.fn(), register: vi.fn(), logout: vi.fn() };
+}
+
+const WhereAmI: FC = () => <span>at {useLocation().pathname}</span>;
+
+function renderLogin(manager: ClientManager): void {
+  render(
+    <MemoryRouter initialEntries={["/login"]}>
+      <ClientManagerProvider value={manager}>
+        <LoginPage />
+        <WhereAmI />
+      </ClientManagerProvider>
+    </MemoryRouter>,
+  );
+}

src/auth/LoginPage.tsx

@@ -11,10 +11,9 @@ import { Trans, useTranslation } from "react-i18next";
 import { Button } from "@vector-im/compound-web";
 
 import Logo from "../icons/LogoLarge.svg?react";
-import { useClient } from "../ClientContext";
+import { useClientManager } from "../ClientContext";
 import { FieldRow, InputField, ErrorMessage } from "../input/Input";
 import styles from "./LoginPage.module.css";
-import { useInteractiveLogin } from "./useInteractiveLogin";
 import { usePageTitle } from "../usePageTitle";
 import { PosthogAnalytics } from "../analytics/PosthogAnalytics";
 import { Config } from "../config/Config";
@@ -24,8 +23,7 @@ export const LoginPage: FC = () => {
   const { t } = useTranslation();
   usePageTitle(t("login_title"));
 
-  const { client, setClient } = useClient();
-  const login = useInteractiveLogin(client);
+  const { login } = useClientManager();
   const homeserver = Config.defaultHomeserverUrl(); // TODO: Make this configurable
   const usernameRef = useRef<HTMLInputElement>(null);
   const passwordRef = useRef<HTMLInputElement>(null);
@@ -46,15 +44,8 @@ export const LoginPage: FC = () => {
         setLoading(false);
         return;
       }
-
       login(homeserver, usernameRef.current.value, passwordRef.current.value)
-        .then(async ([client, session]) => {
-          if (!setClient) {
-            return;
-          }
-
-          setClient(client, session);
-
+        .then(async () => {
           const locationState = location.state;
           // eslint-disable-next-line @typescript-eslint/ban-ts-comment
           // @ts-ignore
@@ -72,7 +63,7 @@ export const LoginPage: FC = () => {
           setLoading(false);
         });
     },
-    [login, location, navigate, homeserver, setClient],
+    [login, location, navigate, homeserver],
   );
   // we need to limit the length of the homserver name to not cover the whole loginview input with the string.
   let shortendHomeserverName = Config.defaultServerName()?.slice(0, 25);

src/auth/RegisterPage.test.tsx

@@ -0,0 +1,133 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { afterEach, expect, test, vi } from "vitest";
+import { render, screen } from "@testing-library/react";
+import userEvent from "@testing-library/user-event";
+import { type FC } from "react";
+import { MemoryRouter, useLocation } from "react-router-dom";
+import { type MatrixClient } from "matrix-js-sdk";
+import { BehaviorSubject } from "rxjs";
+
+import { RegisterPage } from "./RegisterPage";
+import { ClientContextProvider, ClientManagerProvider } from "../ClientContext";
+import {
+  type ClientManager,
+  type ClientSessionState,
+} from "../state/ClientSession";
+
+vi.mock("./useRecaptcha", () => ({
+  useRecaptcha: () => ({
+    execute: vi.fn().mockResolvedValue("captcha-response"),
+    reset,
+    recaptchaId: "recaptcha",
+  }),
+}));
+vi.mock("./useRegistrationTerms", () => ({
+  useRegistrationTerms: () => ({ recaptchaKey: "site-key" }),
+}));
+
+const reset = vi.fn();
+
+afterEach(() => vi.clearAllMocks());
+
+test("waits for the session to be restored", () => {
+  renderRegister({ state: "loading" }, mockManager());
+  expect(screen.getByRole("heading", { name: "Loading…" })).toBeVisible();
+});
+
+test("registers an account, signs in and goes home", async () => {
+  const manager = mockManager();
+  const setSignedIn = vi.fn();
+  vi.mocked(manager.register).mockResolvedValue({
+    client: {} as MatrixClient,
+    setSignedIn,
+  });
+  renderRegister({ state: "signedOut" }, manager);
+
+  await submit("alice", "hunter2");
+
+  expect(manager.register).toHaveBeenCalledWith(
+    "alice",
+    "hunter2",
+    "alice",
+    "captcha-response",
+    false,
+  );
+  expect(setSignedIn).toHaveBeenCalled();
+  expect(await screen.findByText("at /")).toBeVisible();
+});
+
+test("upgrades a passwordless user to a full account", async () => {
+  const manager = mockManager();
+  vi.mocked(manager.register).mockResolvedValue({
+    client: {} as MatrixClient,
+    setSignedIn: vi.fn(),
+  });
+  renderRegister(
+    {
+      state: "signedIn",
+      client: { getUserId: () => "@guest:example.org" } as MatrixClient,
+      passwordlessUser: true,
+    },
+    manager,
+  );
+
+  await submit("alice", "hunter2");
+
+  expect(manager.register).toHaveBeenCalledWith(
+    "alice",
+    "hunter2",
+    "alice",
+    "captcha-response",
+    true,
+  );
+});
+
+test("shows why registering failed and resets the captcha", async () => {
+  const manager = mockManager();
+  vi.mocked(manager.register).mockRejectedValue(new Error("Name taken"));
+  renderRegister({ state: "signedOut" }, manager);
+
+  await submit("alice", "hunter2");
+
+  expect(await screen.findByText("Name taken")).toBeVisible();
+  expect(reset).toHaveBeenCalled();
+  expect(screen.getByText("at /register")).toBeVisible();
+});
+
+async function submit(username: string, password: string): Promise<void> {
+  const user = userEvent.setup();
+  await user.type(screen.getByTestId("register_username"), username);
+  await user.type(screen.getByTestId("register_password"), password);
+  await user.type(screen.getByTestId("register_confirm_password"), password);
+  await user.click(screen.getByTestId("register_register"));
+}
+
+function mockManager(): ClientManager {
+  return { login: vi.fn(), register: vi.fn(), logout: vi.fn() };
+}
+
+const WhereAmI: FC = () => <span>at {useLocation().pathname}</span>;
+
+function renderRegister(
+  state: ClientSessionState,
+  manager: ClientManager,
+): void {
+  render(
+    <MemoryRouter initialEntries={["/register"]}>
+      <ClientContextProvider
+        value={{ state$: new BehaviorSubject<ClientSessionState>(state) }}
+      >
+        <ClientManagerProvider value={manager}>
+          <RegisterPage />
+          <WhereAmI />
+        </ClientManagerProvider>
+      </ClientContextProvider>
+    </MemoryRouter>,
+  );
+}

src/auth/RegisterPage.tsx

@@ -22,8 +22,12 @@ import { logger } from "matrix-js-sdk/lib/logger";
 import { Button, Text } from "@vector-im/compound-web";
 
 import { FieldRow, InputField, ErrorMessage } from "../input/Input";
-import { useClientLegacy } from "../ClientContext";
-import { useInteractiveRegistration } from "./useInteractiveRegistration";
+import {
+  useClient,
+  useClientManager,
+  useClientSessionState,
+} from "../ClientContext";
+import { useRegistrationTerms } from "./useRegistrationTerms";
 import styles from "./LoginPage.module.css";
 import Logo from "../icons/LogoLarge.svg?react";
 import { LoadingPage } from "../FullScreenView";
@@ -37,8 +41,13 @@ export const RegisterPage: FC = () => {
   const { t } = useTranslation();
   usePageTitle(t("action.register"));
 
-  const { loading, authenticated, passwordlessUser, client, setClient } =
-    useClientLegacy();
+  const session = useClientSessionState();
+  const loading = session.state === "loading";
+  const passwordlessUser =
+    session.state === "signedIn" && session.passwordlessUser;
+  const { client } = useClient();
+  const authenticated = client !== undefined;
+  const { register } = useClientManager();
 
   const confirmPasswordRef = useRef<HTMLInputElement>(null);
   const navigate = useNavigate();
@@ -47,7 +56,7 @@ export const RegisterPage: FC = () => {
   const [error, setError] = useState<Error>();
   const [password, setPassword] = useState("");
   const [passwordConfirmation, setPasswordConfirmation] = useState("");
-  const { recaptchaKey, register } = useInteractiveRegistration(client);
+  const { recaptchaKey } = useRegistrationTerms();
   const { execute, reset, recaptchaId } = useRecaptcha(recaptchaKey);
 
   const onSubmitRegisterForm = useCallback(
@@ -64,7 +73,7 @@ export const RegisterPage: FC = () => {
         setRegistering(true);
 
         const recaptchaResponse = await execute();
-        const [newClient, session] = await register(
+        const { client: newClient, setSignedIn } = await register(
           userName,
           password,
           userName,
@@ -95,7 +104,7 @@ export const RegisterPage: FC = () => {
           }
         }
 
-        setClient?.(newClient, session);
+        setSignedIn();
         PosthogAnalytics.instance.eventSignup.cacheSignupEnd(new Date());
       };
 
@@ -117,16 +126,7 @@ export const RegisterPage: FC = () => {
           reset();
         });
     },
-    [
-      register,
-      location,
-      navigate,
-      passwordlessUser,
-      reset,
-      execute,
-      client,
-      setClient,
-    ],
+    [register, location, navigate, passwordlessUser, reset, execute, client],
   );
 
   useEffect(() => {

src/auth/interactiveAuth.test.ts

@@ -0,0 +1,104 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { afterEach, expect, test, vi } from "vitest";
+import { createClient, type MatrixClient, MatrixError } from "matrix-js-sdk";
+import type * as MatrixJsSdk from "matrix-js-sdk";
+
+import { loginWithPassword, registerWithPassword } from "./interactiveAuth";
+
+vi.mock("matrix-js-sdk", async (importOriginal) => ({
+  ...(await importOriginal<typeof MatrixJsSdk>()),
+  createClient: vi.fn(),
+}));
+
+const credentials = {
+  user_id: "@alice:example.org",
+  device_id: "AAAA",
+  access_token: "secret",
+};
+
+// What interactive auth asks of the client besides the request itself
+const authClient = { generateClientSecret: () => "client-secret" };
+
+afterEach(() => {
+  vi.clearAllMocks();
+});
+
+test("logs in with a password", async () => {
+  const login = vi.fn().mockResolvedValue({ ...credentials, extra: "ignored" });
+  vi.mocked(createClient).mockReturnValue({
+    ...authClient,
+    login,
+  } as Partial<MatrixClient> as MatrixClient);
+
+  await expect(
+    loginWithPassword("https://hs.example.org", "alice", "hunter2"),
+  ).resolves.toEqual(credentials);
+
+  expect(createClient).toHaveBeenCalledWith({
+    baseUrl: "https://hs.example.org",
+  });
+  expect(login).toHaveBeenCalledWith("m.login.password", {
+    identifier: { type: "m.id.user", user: "alice" },
+    password: "hunter2",
+  });
+});
+
+test("registers, agreeing to the terms and answering the recaptcha", async () => {
+  // The homeserver turns the first request away with the stages to complete
+  // No error in it: that is the shape of a challenge rather than a refusal
+  const challenge = new MatrixError(
+    {
+      session: "session",
+      flows: [{ stages: ["m.login.terms", "m.login.recaptcha"] }],
+      params: {},
+      completed: [],
+    },
+    401,
+  );
+  const registerRequest = vi
+    .fn()
+    .mockImplementation(({ auth }: { auth?: { type: string } }) => {
+      if (auth === undefined) throw challenge;
+      challenge.data.completed = [
+        ...(challenge.data.completed as string[]),
+        auth.type,
+      ];
+      if (challenge.data.completed.length < 2) throw challenge;
+      return credentials;
+    });
+  vi.mocked(createClient).mockReturnValue({
+    ...authClient,
+    registerRequest,
+  } as Partial<MatrixClient> as MatrixClient);
+
+  await expect(
+    registerWithPassword(
+      "https://hs.example.org",
+      "alice",
+      "hunter2",
+      "captcha",
+    ),
+  ).resolves.toEqual(credentials);
+
+  expect(registerRequest).toHaveBeenCalledWith(
+    expect.objectContaining({
+      username: "alice",
+      password: "hunter2",
+      auth: expect.objectContaining({ type: "m.login.terms" }),
+    }),
+  );
+  expect(registerRequest).toHaveBeenCalledWith(
+    expect.objectContaining({
+      auth: expect.objectContaining({
+        type: "m.login.recaptcha",
+        response: "captcha",
+      }),
+    }),
+  );
+});

src/auth/interactiveAuth.ts

@@ -0,0 +1,106 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import {
+  createClient,
+  InteractiveAuth,
+  type LoginResponse,
+  type RegisterResponse,
+} from "matrix-js-sdk";
+import { logger } from "matrix-js-sdk/lib/logger";
+
+import { type StoredSession } from "../state/ClientSession";
+
+/** What the homeserver hands out for a new session. */
+export type Credentials = Pick<
+  StoredSession,
+  "user_id" | "device_id" | "access_token"
+>;
+
+/**
+ * Logs in to the given homeserver with a password.
+ */
+export async function loginWithPassword(
+  homeserver: string,
+  username: string,
+  password: string,
+): Promise<Credentials> {
+  const authClient = createClient({ baseUrl: homeserver });
+  const interactiveAuth = new InteractiveAuth({
+    matrixClient: authClient,
+    doRequest: async (): Promise<LoginResponse> =>
+      authClient.login("m.login.password", {
+        identifier: {
+          type: "m.id.user",
+          user: username,
+        },
+        password,
+      }),
+    stateUpdated: (): void => {},
+    requestEmailToken: async (): Promise<{ sid: string }> =>
+      Promise.resolve({ sid: "" }),
+  });
+  return credentials(await interactiveAuth.attemptAuth());
+}
+
+/**
+ * Registers an account on the given homeserver, accepting its terms and
+ * answering its recaptcha challenge.
+ */
+export async function registerWithPassword(
+  homeserver: string,
+  username: string,
+  password: string,
+  recaptchaResponse: string,
+): Promise<Credentials> {
+  const authClient = createClient({ baseUrl: homeserver });
+  const interactiveAuth = new InteractiveAuth({
+    matrixClient: authClient,
+    doRequest: async (auth): Promise<RegisterResponse> =>
+      authClient.registerRequest({
+        username,
+        password,
+        auth: auth || undefined,
+      }),
+    stateUpdated: (nextStage, status): void => {
+      if (status.error) {
+        throw new Error(status.error);
+      }
+
+      if (nextStage === "m.login.terms") {
+        interactiveAuth
+          .submitAuthDict({
+            type: "m.login.terms",
+          })
+          .catch((e) => {
+            logger.error(e);
+          });
+      } else if (nextStage === "m.login.recaptcha") {
+        interactiveAuth
+          .submitAuthDict({
+            type: "m.login.recaptcha",
+            response: recaptchaResponse,
+          })
+          .catch((e) => {
+            logger.error(e);
+          });
+      }
+    },
+    requestEmailToken: async (): Promise<{ sid: string }> =>
+      Promise.resolve({ sid: "dummy" }),
+  });
+  return credentials(await interactiveAuth.attemptAuth());
+}
+
+// XXX: attemptAuth claims to return an IAuthData which contains none of these
+// things - the js-sdk types may be wrong?
+function credentials(authData: unknown): Credentials {
+  /* eslint-disable camelcase */
+  const { user_id, access_token, device_id } = authData as Credentials;
+  return { user_id, access_token, device_id };
+  /* eslint-enable camelcase */
+}

src/auth/useInteractiveLogin.ts

@@ -1,84 +0,0 @@
-/*
-Copyright 2022-2024 New Vector Ltd.
-
-SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
-Please see LICENSE in the repository root for full details.
-*/
-
-import { useCallback } from "react";
-import { InteractiveAuth } from "matrix-js-sdk";
-import {
-  createClient,
-  type LoginResponse,
-  type MatrixClient,
-} from "matrix-js-sdk";
-
-import { initClient } from "../utils/matrix";
-import { type Session } from "../ClientContext";
-/**
- * This provides the login method to login using user credentials.
- * @param oldClient If there is an already authenticated client it should be passed to this hook
- * this allows the interactive login to sign out the client before logging in.
- * @returns A async method that can be called/awaited to log in with the provided credentials.
- */
-export function useInteractiveLogin(
-  oldClient?: MatrixClient,
-): (
-  homeserver: string,
-  username: string,
-  password: string,
-) => Promise<[MatrixClient, Session]> {
-  return useCallback<
-    (
-      homeserver: string,
-      username: string,
-      password: string,
-    ) => Promise<[MatrixClient, Session]>
-  >(
-    async (homeserver: string, username: string, password: string) => {
-      const authClient = createClient({ baseUrl: homeserver });
-
-      const interactiveAuth = new InteractiveAuth({
-        matrixClient: authClient,
-        doRequest: async (): Promise<LoginResponse> =>
-          authClient.login("m.login.password", {
-            identifier: {
-              type: "m.id.user",
-              user: username,
-            },
-            password,
-          }),
-        stateUpdated: (): void => {},
-        requestEmailToken: async (): Promise<{ sid: string }> =>
-          Promise.resolve({ sid: "" }),
-      });
-
-      // XXX: This claims to return an IAuthData which contains none of these
-      // things - the js-sdk types may be wrong?
-      /* eslint-disable camelcase,@typescript-eslint/no-explicit-any */
-      const { user_id, access_token, device_id } =
-        (await interactiveAuth.attemptAuth()) as any;
-      const session = {
-        user_id,
-        access_token,
-        device_id,
-        passwordlessUser: false,
-      };
-
-      // To not confuse the rust crypto sessions we need to logout the old client before initializing the new one.
-      await oldClient?.logout(true);
-      const client = await initClient(
-        {
-          baseUrl: homeserver,
-          accessToken: access_token,
-          userId: user_id,
-          deviceId: device_id,
-        },
-        false,
-      );
-      /* eslint-enable camelcase */
-      return [client, session];
-    },
-    [oldClient],
-  );
-}

src/auth/useInteractiveRegistration.ts

@@ -1,145 +0,0 @@
-/*
-Copyright 2022-2024 New Vector Ltd.
-
-SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
-Please see LICENSE in the repository root for full details.
-*/
-
-import { useState, useEffect, useCallback, useRef } from "react";
-import { InteractiveAuth } from "matrix-js-sdk";
-import {
-  createClient,
-  type MatrixClient,
-  type RegisterResponse,
-} from "matrix-js-sdk";
-import { logger } from "matrix-js-sdk/lib/logger";
-
-import { initClient } from "../utils/matrix";
-import { type Session } from "../ClientContext";
-import { Config } from "../config/Config";
-import { useUrlParams } from "../UrlParams";
-
-export const useInteractiveRegistration = (
-  oldClient?: MatrixClient,
-): {
-  privacyPolicyUrl?: string;
-  recaptchaKey?: string;
-  register: (
-    username: string,
-    password: string,
-    displayName: string,
-    recaptchaResponse: string,
-    passwordlessUser: boolean,
-  ) => Promise<[MatrixClient, Session]>;
-} => {
-  const { isWidget } = useUrlParams();
-  const [privacyPolicyUrl, setPrivacyPolicyUrl] = useState<string | undefined>(
-    undefined,
-  );
-  const [recaptchaKey, setRecaptchaKey] = useState<string | undefined>(
-    undefined,
-  );
-
-  const authClient = useRef<MatrixClient | undefined>(undefined);
-  if (!authClient.current) {
-    authClient.current = createClient({
-      baseUrl: Config.defaultHomeserverUrl()!,
-    });
-  }
-
-  useEffect(() => {
-    if (isWidget) return;
-    // An empty registerRequest is used to get the privacy policy and recaptcha key.
-    authClient.current!.registerRequest({}).catch((error) => {
-      setPrivacyPolicyUrl(
-        error.data?.params["m.login.terms"]?.policies?.privacy_policy?.en?.url,
-      );
-      setRecaptchaKey(error.data?.params["m.login.recaptcha"]?.public_key);
-    });
-  }, [isWidget]);
-
-  const register = useCallback(
-    async (
-      username: string,
-      password: string,
-      displayName: string,
-      recaptchaResponse: string,
-      passwordlessUser: boolean,
-    ): Promise<[MatrixClient, Session]> => {
-      const interactiveAuth = new InteractiveAuth({
-        matrixClient: authClient.current!,
-        doRequest: async (auth): Promise<RegisterResponse> =>
-          authClient.current!.registerRequest({
-            username,
-            password,
-            auth: auth || undefined,
-          }),
-        stateUpdated: (nextStage, status): void => {
-          if (status.error) {
-            throw new Error(status.error);
-          }
-
-          if (nextStage === "m.login.terms") {
-            interactiveAuth
-              .submitAuthDict({
-                type: "m.login.terms",
-              })
-              .catch((e) => {
-                logger.error(e);
-              });
-          } else if (nextStage === "m.login.recaptcha") {
-            interactiveAuth
-              .submitAuthDict({
-                type: "m.login.recaptcha",
-                response: recaptchaResponse,
-              })
-              .catch((e) => {
-                logger.error(e);
-              });
-          }
-        },
-        requestEmailToken: async (): Promise<{ sid: string }> =>
-          Promise.resolve({ sid: "dummy" }),
-      });
-
-      // XXX: This claims to return an IAuthData which contains none of these
-      // things - the js-sdk types may be wrong?
-      /* eslint-disable camelcase,@typescript-eslint/no-explicit-any */
-      const { user_id, access_token, device_id } =
-        (await interactiveAuth.attemptAuth()) as any;
-      await oldClient?.logout(true);
-      const client = await initClient(
-        {
-          baseUrl: Config.defaultHomeserverUrl()!,
-          accessToken: access_token,
-          userId: user_id,
-          deviceId: device_id,
-        },
-        false,
-      );
-
-      await client.setDisplayName(displayName);
-
-      const session: Session = {
-        user_id,
-        device_id,
-        access_token,
-        passwordlessUser,
-      };
-      /* eslint-enable camelcase */
-
-      if (passwordlessUser) {
-        session.tempPassword = password;
-      }
-
-      const user = client.getUser(client.getUserId()!)!;
-      user.setRawDisplayName(displayName);
-      user.setDisplayName(displayName);
-
-      return [client, session];
-    },
-    [oldClient],
-  );
-
-  return { privacyPolicyUrl, recaptchaKey, register };
-};

src/auth/useRegisterPasswordlessUser.test.tsx

@@ -0,0 +1,116 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { afterEach, expect, test, vi } from "vitest";
+import { renderHook } from "@testing-library/react";
+import { type FC, type PropsWithChildren } from "react";
+import { type MatrixClient } from "matrix-js-sdk";
+
+import { useRegisterPasswordlessUser } from "./useRegisterPasswordlessUser";
+import { ClientManagerProvider } from "../ClientContext";
+import { type ClientManager } from "../state/ClientSession";
+import { computeUrlParams, UrlParamsProvider } from "../UrlParams";
+
+vi.mock("./useRecaptcha", () => ({
+  useRecaptcha: () => ({
+    execute: vi.fn().mockResolvedValue("captcha-response"),
+    reset,
+    recaptchaId: "recaptcha",
+  }),
+}));
+vi.mock("./useRegistrationTerms", () => ({
+  useRegistrationTerms: () => ({
+    privacyPolicyUrl: "https://hs.example.org/privacy",
+    recaptchaKey: "site-key",
+  }),
+}));
+vi.mock("./generateRandomName", () => ({
+  generateRandomName: () => "Random Name",
+}));
+
+const reset = vi.fn();
+
+afterEach(() => vi.clearAllMocks());
+
+test("registers a user under a random name and signs them in", async () => {
+  const setSignedIn = vi.fn();
+  const manager = mockManager();
+  vi.mocked(manager.register).mockResolvedValue({
+    client: {} as MatrixClient,
+    setSignedIn,
+  });
+
+  const { result } = renderHook(() => useRegisterPasswordlessUser(), {
+    wrapper: wrapper(manager, false),
+  });
+  await result.current.registerPasswordlessUser("Alice");
+
+  expect(manager.register).toHaveBeenCalledWith(
+    "Random Name",
+    expect.stringMatching(/^.{16}$/),
+    "Alice",
+    "captcha-response",
+    true,
+  );
+  expect(setSignedIn).toHaveBeenCalled();
+  expect(result.current.privacyPolicyUrl).toBe(
+    "https://hs.example.org/privacy",
+  );
+  expect(result.current.recaptchaId).toBe("recaptcha");
+});
+
+test("resets the captcha when registration fails", async () => {
+  const manager = mockManager();
+  vi.mocked(manager.register).mockRejectedValue(new Error("Nope"));
+
+  const { result } = renderHook(() => useRegisterPasswordlessUser(), {
+    wrapper: wrapper(manager, false),
+  });
+
+  await expect(
+    result.current.registerPasswordlessUser("Alice"),
+  ).rejects.toThrow("Nope");
+  expect(reset).toHaveBeenCalled();
+});
+
+test("cannot register on a session that is not ours", async () => {
+  const { result } = renderHook(() => useRegisterPasswordlessUser(), {
+    wrapper: wrapper(null, false),
+  });
+
+  await expect(
+    result.current.registerPasswordlessUser("Alice"),
+  ).rejects.toThrow("This session cannot register");
+});
+
+test("never registers as a widget", async () => {
+  const manager = mockManager();
+  const { result } = renderHook(() => useRegisterPasswordlessUser(), {
+    wrapper: wrapper(manager, true),
+  });
+
+  await expect(
+    result.current.registerPasswordlessUser("Alice"),
+  ).rejects.toThrow(/embedded mode/);
+  expect(manager.register).not.toHaveBeenCalled();
+});
+
+function mockManager(): ClientManager {
+  return { login: vi.fn(), register: vi.fn(), logout: vi.fn() };
+}
+
+function wrapper(
+  manager: ClientManager | null,
+  isWidget: boolean,
+): FC<PropsWithChildren> {
+  const params = { ...computeUrlParams(), isWidget };
+  return ({ children }) => (
+    <UrlParamsProvider value={params}>
+      <ClientManagerProvider value={manager}>{children}</ClientManagerProvider>
+    </UrlParamsProvider>
+  );
+}

src/auth/useRegisterPasswordlessUser.ts

@@ -8,8 +8,8 @@ Please see LICENSE in the repository root for full details.
 import { useCallback } from "react";
 import { secureRandomString } from "matrix-js-sdk/lib/randomstring";
 
-import { useClient } from "../ClientContext";
-import { useInteractiveRegistration } from "../auth/useInteractiveRegistration";
+import { useClientManagerIfAny } from "../ClientContext";
+import { useRegistrationTerms } from "../auth/useRegistrationTerms";
 import { generateRandomName } from "../auth/generateRandomName";
 import { useRecaptcha } from "../auth/useRecaptcha";
 import { useUrlParams } from "../UrlParams";
@@ -21,16 +21,16 @@ interface UseRegisterPasswordlessUserType {
 }
 
 export function useRegisterPasswordlessUser(): UseRegisterPasswordlessUserType {
-  const { setClient } = useClient();
+  // Null in the widget, which never registers anyone
+  const register = useClientManagerIfAny()?.register;
   const { isWidget } = useUrlParams();
-  const { privacyPolicyUrl, recaptchaKey, register } =
-    useInteractiveRegistration();
+  const { privacyPolicyUrl, recaptchaKey } = useRegistrationTerms();
   const { execute, reset, recaptchaId } = useRecaptcha(recaptchaKey);
 
   const registerPasswordlessUser = useCallback(
     async (displayName: string) => {
-      if (!setClient) {
-        throw new Error("No client context");
+      if (!register) {
+        throw new Error("This session cannot register");
       }
       if (isWidget) {
         throw new Error(
@@ -41,20 +41,20 @@ export function useRegisterPasswordlessUser(): UseRegisterPasswordlessUserType {
       try {
         const recaptchaResponse = await execute();
         const userName = generateRandomName();
-        const [client, session] = await register(
+        const { setSignedIn } = await register(
           userName,
           secureRandomString(16),
           displayName,
           recaptchaResponse,
           true,
         );
-        setClient(client, session);
+        setSignedIn();
       } catch (e) {
         reset();
         throw e;
       }
     },
-    [execute, reset, register, setClient, isWidget],
+    [execute, reset, register, isWidget],
   );
 
   return { privacyPolicyUrl, registerPasswordlessUser, recaptchaId };

src/auth/useRegistrationTerms.test.tsx

@@ -0,0 +1,98 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { afterEach, beforeEach, expect, test, vi } from "vitest";
+import { renderHook, waitFor } from "@testing-library/react";
+import type * as MatrixJsSdk from "matrix-js-sdk";
+import { createClient, type MatrixClient } from "matrix-js-sdk";
+import { type FC, type PropsWithChildren } from "react";
+
+import { useRegistrationTerms } from "./useRegistrationTerms";
+import { computeUrlParams, UrlParamsProvider } from "../UrlParams";
+import { Config } from "../config/Config";
+
+vi.mock("matrix-js-sdk", async (importOriginal) => ({
+  ...(await importOriginal<typeof MatrixJsSdk>()),
+  createClient: vi.fn(),
+}));
+
+const registerRequest = vi.fn();
+
+beforeEach(() => {
+  vi.spyOn(Config, "defaultHomeserverUrl").mockReturnValue(
+    "https://hs.example.org",
+  );
+  vi.mocked(createClient).mockReturnValue({
+    registerRequest,
+  } as Partial<MatrixClient> as MatrixClient);
+});
+afterEach(() => {
+  vi.restoreAllMocks();
+  vi.clearAllMocks();
+});
+
+test("reads the terms the homeserver asks for from a registration attempt", async () => {
+  registerRequest.mockRejectedValue({
+    data: {
+      params: {
+        "m.login.terms": {
+          policies: {
+            privacy_policy: { en: { url: "https://hs.example.org/privacy" } },
+          },
+        },
+        "m.login.recaptcha": { public_key: "site-key" },
+      },
+    },
+  });
+
+  const { result } = renderHook(() => useRegistrationTerms(), {
+    wrapper: wrapper(false),
+  });
+
+  expect(createClient).toHaveBeenCalledWith({
+    baseUrl: "https://hs.example.org",
+  });
+  await waitFor(() =>
+    expect(result.current).toEqual({
+      privacyPolicyUrl: "https://hs.example.org/privacy",
+      recaptchaKey: "site-key",
+    }),
+  );
+});
+
+test("has nothing to agree to where the homeserver asks for nothing", async () => {
+  registerRequest.mockRejectedValue({ data: { params: {} } });
+
+  const { result } = renderHook(() => useRegistrationTerms(), {
+    wrapper: wrapper(false),
+  });
+
+  await waitFor(() => expect(registerRequest).toHaveBeenCalled());
+  expect(result.current).toEqual({
+    privacyPolicyUrl: undefined,
+    recaptchaKey: undefined,
+  });
+});
+
+test("asks the homeserver nothing as a widget", () => {
+  const { result } = renderHook(() => useRegistrationTerms(), {
+    wrapper: wrapper(true),
+  });
+
+  expect(createClient).not.toHaveBeenCalled();
+  expect(result.current).toEqual({
+    privacyPolicyUrl: undefined,
+    recaptchaKey: undefined,
+  });
+});
+
+function wrapper(isWidget: boolean): FC<PropsWithChildren> {
+  const params = { ...computeUrlParams(), isWidget };
+  return ({ children }) => (
+    <UrlParamsProvider value={params}>{children}</UrlParamsProvider>
+  );
+}

src/auth/useRegistrationTerms.ts

@@ -0,0 +1,46 @@
+/*
+Copyright 2022-2024 New Vector Ltd.
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { useEffect, useState } from "react";
+import { createClient } from "matrix-js-sdk";
+
+import { Config } from "../config/Config";
+import { useUrlParams } from "../UrlParams";
+
+/**
+ * What the homeserver asks of a registration: its privacy policy to agree to
+ * and the recaptcha key to answer a challenge with.
+ */
+export function useRegistrationTerms(): {
+  privacyPolicyUrl?: string;
+  recaptchaKey?: string;
+} {
+  const { isWidget } = useUrlParams();
+  const [privacyPolicyUrl, setPrivacyPolicyUrl] = useState<string | undefined>(
+    undefined,
+  );
+  const [recaptchaKey, setRecaptchaKey] = useState<string | undefined>(
+    undefined,
+  );
+
+  useEffect(() => {
+    if (isWidget) return;
+    // An empty registerRequest is used to get the privacy policy and recaptcha key.
+    createClient({ baseUrl: Config.defaultHomeserverUrl()! })
+      .registerRequest({})
+      .catch((error) => {
+        setPrivacyPolicyUrl(
+          error.data?.params["m.login.terms"]?.policies?.privacy_policy?.en
+            ?.url,
+        );
+        setRecaptchaKey(error.data?.params["m.login.recaptcha"]?.public_key);
+      });
+  }, [isWidget]);
+
+  return { privacyPolicyUrl, recaptchaKey };
+}

src/components/BackgroundEffectGrid.tsx

@@ -45,7 +45,7 @@ interface Props {
   /** Offers to add a background of one's own. Omit to leave that tile out. */
   onAdd?: () => void;
   addLabel?: string;
-  /** Removes a removable one, unless it is the selected one. Omit to offer none. */
+  /** Removes a removable one, never the one in force. Omit to offer none. */
   onRemove?: (id: string) => void;
   removeLabel?: string;
 }

src/components/CallFooter.stories.tsx

@@ -22,7 +22,7 @@ import { MediaDevices } from "../state/MediaDevices";
 import { globalScope } from "../state/ObservableScope";
 import { constant } from "../state/Behavior";
 import { type LayoutMode } from "../state/LayoutSwitchViewModel";
-import { type MediaMenuSnapshot } from "./MediaMenuViewModel";
+import { shippedBackgrounds } from "../tracks/backgroundEffectCatalog";
 
 // consts for tests
 const reactionIdentifier = "@user:example.com:DEVICE";
@@ -35,57 +35,10 @@ const mediaDevices = new MediaDevices(globalScope, {
   controlledAudioDevices: false,
 });
 
-function menu(
-  kind: "audio" | "video",
-  withDevices: boolean,
-): MediaMenuSnapshot {
-  const device = kind === "audio" ? "Microphone" : "Camera";
-  return {
-    enabled: true,
-    busy: false,
-    toggle: fn(),
-    options: withDevices
-      ? [
-          { id: "1", label: { type: "name", name: `${device} 1` } },
-          { id: "2", label: { type: "name", name: `${device} 2` } },
-        ]
-      : [],
-    selected: "1",
-    select: fn(),
-    outputOptions:
-      withDevices && kind === "audio"
-        ? [
-            {
-              id: "default",
-              label: { type: "default", name: "Built-in Output" },
-            },
-          ]
-        : [],
-    selectedOutput: "default",
-    selectOutput: fn(),
-    backgroundEffect: "none",
-    backgroundEffects:
-      kind === "video"
-        ? [
-            { id: "none", kind: "none" },
-            { id: "blur", kind: "blur" },
-          ]
-        : [],
-    backgroundEffectNotice: undefined,
-    backgroundEffectSettling: false,
-    backgroundImageRefusal: undefined,
-    selectBackgroundEffect: fn(),
-    addBackgroundImage: undefined,
-    removeBackgroundEffect: undefined,
-    cameraTrack: null,
-  };
-}
-
 /**
  * A wrapper component that is used for:
  *  - exposing the snapshot via props so the storybook documents the snapshot properties (basically unpack them form the vm)
- *  - constructing the layout switch and the menus' view models; the menus'
- *    own states are in the MediaMenuButton stories
+ *  - constructing the layout switch view model
  *  - Add additional react context
  * The paraeters are all params from the FooterSnapshot,
  * the Snapshot of the vm, the wrapper will create a mocked vm from it and pass it to the CallFooter.
@@ -96,22 +49,15 @@ function CallFooterStoryWrapper({
   children,
   layout,
   setLayout,
-  withDevices,
   ...vmSnapshot
-}: Omit<FooterSnapshot, "layoutSwitchVm" | "audioMenuVm" | "cameraMenuVm"> & {
+}: Omit<FooterSnapshot, "layoutSwitchVm"> & {
   children?: false | JSX.Element | JSX.Element[] | undefined;
   layout: LayoutMode | null;
   setLayout: (value: LayoutMode) => void;
-  /** Whether the menus have devices to pick, or are plain mute buttons. */
-  withDevices: boolean;
 }): ReactNode {
-  const audioMenuVm = useStaticViewModel(menu("audio", withDevices));
-  const cameraMenuVm = useStaticViewModel(menu("video", withDevices));
   const vm = useStaticViewModel({
     ...vmSnapshot,
     layoutSwitchVm: layout && { layout$: constant(layout), setLayout },
-    audioMenuVm,
-    cameraMenuVm,
   });
   return (
     <MediaDevicesContext value={mediaDevices}>
@@ -156,6 +102,8 @@ const meta = {
     },
     toggleScreenSharing: fnArgType,
     openSettings: fnArgType,
+    toggleAudio: fnArgType,
+    toggleVideo: fnArgType,
     hangup: fnArgType,
   },
 } satisfies Meta<typeof CallFooterStoryWrapper>;
@@ -168,9 +116,32 @@ export const Default: Story = {
     showLogo: false,
     layout: "grid",
     setLayout: fn(),
-    withDevices: false,
+    audioEnabled: true,
+    audioBusy: false,
+    videoEnabled: true,
+    videoBusy: false,
     openSettings: fn(),
+    toggleAudio: fn(),
+    toggleVideo: fn(),
     toggleScreenSharing: fn(),
+    selectBackgroundEffect: fn(),
+    backgroundEffect: "blur",
+    backgroundEffects: [
+      { id: "none", kind: "none", removable: false },
+      { id: "blur", kind: "blur", removable: false },
+      ...shippedBackgrounds.map((background) => ({
+        id: `image:${background.id}`,
+        kind: "image" as const,
+        imageUrl: background.imagePath,
+        removable: false,
+      })),
+    ],
+    backgroundEffectNotice: undefined,
+    backgroundEffectSettling: false,
+    backgroundImageRefusal: undefined,
+    addBackgroundImage: fn(),
+    removeBackgroundEffect: fn(),
+    cameraTrack: null,
     hangup: fn(),
     buttonSize: "lg",
     showFooter: true,
@@ -183,17 +154,49 @@ export const Default: Story = {
     reactionData: undefined,
     debugTileLayout: false,
     tileStoreGeneration: undefined,
+    audioOptions: [],
+    audioOutputOptions: [],
+    videoOptions: [],
+    selectedAudio: undefined,
+    selectedAudioOutput: undefined,
+    selectedVideo: undefined,
+    selectAudioButtonOption: undefined,
+    selectAudioOutputOption: undefined,
+    selectVideoButtonOption: undefined,
   },
   parameters: {
     layout: "fullscreen",
   },
 };
 
-export const StaysWhileAMenuIsOpen: Story = {
+export const WithAudioAndVideoOptions: Story = {
   ...Default,
   args: {
     ...Default.args,
-    withDevices: true,
+    audioEnabled: false,
+    videoEnabled: true,
+    audioOptions: [
+      { label: { type: "name", name: "Microphone 1" }, id: "1" },
+      { label: { type: "name", name: "Microphone 2" }, id: "2" },
+    ],
+    audioOutputOptions: [
+      { label: { type: "default", name: "Built-in Output" }, id: "default" },
+      { label: { type: "name", name: "Headset" }, id: "2" },
+    ],
+    videoOptions: [
+      { label: { type: "name", name: "Camera 1" }, id: "1" },
+      { label: { type: "name", name: "Camera 2" }, id: "2" },
+    ],
+    selectedAudio: "2",
+    selectedAudioOutput: "default",
+    selectedVideo: "1",
+  },
+};
+
+export const StaysWhileAMenuIsOpen: Story = {
+  ...Default,
+  args: {
+    ...WithAudioAndVideoOptions.args,
     // In a short window the footer overlays the call and hides itself.
     asOverlay: true,
     showFooter: true,
@@ -216,6 +219,25 @@ export const StaysWhileAMenuIsOpen: Story = {
   },
 };
 
+export const AudioBusy: Story = {
+  ...Default,
+  args: {
+    ...Default.args,
+    audioEnabled: true,
+    audioBusy: true,
+    videoEnabled: true,
+  },
+};
+
+export const VideoBusy: Story = {
+  ...Default,
+  args: {
+    ...Default.args,
+    audioEnabled: true,
+    videoEnabled: true,
+    videoBusy: true,
+  },
+};
 export const WithLogo: Story = {
   ...Default,
   args: {
@@ -224,7 +246,45 @@ export const WithLogo: Story = {
   },
 };
 
-/** Switching to grid, and the footer's own buttons, act. */
+export const AudioVideoEnabled: Story = {
+  ...Default,
+  args: {
+    ...Default.args,
+    audioEnabled: true,
+    videoEnabled: true,
+  },
+  play: async ({ args, canvasElement }) => {
+    const canvas = within(canvasElement);
+
+    const spotlightRadio = canvas.getByRole("radio", { name: "Spotlight" });
+    await userEvent.click(spotlightRadio);
+    await expect(args.setLayout).toHaveBeenCalledWith("spotlight");
+
+    const micButtonMute = canvas.getByRole("switch", {
+      name: "Mute microphone",
+    });
+    await userEvent.click(micButtonMute);
+    await expect(args.toggleAudio).toHaveBeenCalled();
+
+    const videoMuteButton = canvas.getByRole("switch", {
+      name: "Stop video",
+    });
+    await userEvent.click(videoMuteButton);
+    await expect(args.toggleVideo).toHaveBeenCalled();
+    const screenShare = canvas.getByRole("switch", {
+      name: "Share screen",
+    });
+    await userEvent.click(screenShare);
+    await expect(args.toggleScreenSharing).toHaveBeenCalled();
+    const endCall = canvas.getByRole("button", {
+      name: "End call",
+    });
+    await userEvent.click(endCall);
+    await expect(args.hangup).toHaveBeenCalled();
+  },
+};
+
+/** used to test switching to grid mode */
 export const SpotlightMode: Story = {
   ...Default,
   args: {
@@ -233,12 +293,10 @@ export const SpotlightMode: Story = {
   },
   play: async ({ args, canvasElement }) => {
     const canvas = within(canvasElement);
-    await userEvent.click(canvas.getByRole("radio", { name: "Grid" }));
+
+    const spotlightRadio = canvas.getByRole("radio", { name: "Grid" });
+    await userEvent.click(spotlightRadio);
     await expect(args.setLayout).toHaveBeenCalledWith("grid");
-    await userEvent.click(canvas.getByRole("switch", { name: "Share screen" }));
-    await expect(args.toggleScreenSharing).toHaveBeenCalled();
-    await userEvent.click(canvas.getByRole("button", { name: "End call" }));
-    await expect(args.hangup).toHaveBeenCalled();
   },
 };
 
@@ -272,10 +330,34 @@ export const Pip: Story = {
     buttonSize: "md",
     layout: null,
   },
-  play: async ({ canvasElement }) => {
+  play: async ({ args, canvasElement }) => {
+    const canvas = within(canvasElement);
+
     await expect(
-      within(canvasElement).queryByRole("radio", { name: "Spotlight" }),
+      canvas.queryByRole("radio", { name: "Spotlight" }),
     ).not.toBeInTheDocument();
+
+    const micButtonMute = canvas.getByRole("switch", {
+      name: "Mute microphone",
+    });
+    await userEvent.click(micButtonMute);
+    await expect(args.toggleAudio).toHaveBeenCalled();
+
+    const videoMuteButton = canvas.getByRole("switch", {
+      name: "Stop video",
+    });
+    await userEvent.click(videoMuteButton);
+    await expect(args.toggleVideo).toHaveBeenCalled();
+    const screenShare = canvas.getByRole("switch", {
+      name: "Share screen",
+    });
+    await userEvent.click(screenShare);
+    await expect(args.toggleScreenSharing).toHaveBeenCalled();
+    const endCall = canvas.getByRole("button", {
+      name: "End call",
+    });
+    await userEvent.click(endCall);
+    await expect(args.hangup).toHaveBeenCalled();
   },
 };
 export const NoControlsWithLogo: Story = {
@@ -296,6 +378,18 @@ export const DebugData: Story = {
   },
 };
 
+export const UnavailableMediaDevices: Story = {
+  ...Default,
+  args: {
+    ...Default.args,
+    audioEnabled: false,
+    videoEnabled: false,
+    toggleAudio: undefined,
+    toggleVideo: undefined,
+    audioOutputSwitcher: undefined,
+  },
+};
+
 export const MobileLayout: Story = {
   ...Default,
   args: {
@@ -326,6 +420,37 @@ export const Lobby: Story = {
   },
 };
 
+export const LobbyMobile: Story = {
+  ...Default,
+  args: {
+    ...Default.args,
+    showLogo: false,
+
+    layout: null,
+    toggleScreenSharing: undefined,
+  },
+  globals: {
+    viewport: { value: "mobile2", isRotated: false },
+  },
+  parameters: {
+    ...Default.parameters,
+  },
+};
+
+export const LobbyRecentButton: Story = {
+  ...Default,
+  args: {
+    ...Default.args,
+    children: <Link>Back To Recents</Link>,
+    showLogo: false,
+    layout: null,
+    toggleScreenSharing: undefined,
+  },
+  parameters: {
+    ...Default.parameters,
+  },
+};
+
 export const LobbyRecentButtonMobile: Story = {
   ...Default,
   args: {

src/components/CallFooter.tsx

@@ -7,11 +7,14 @@ Please see LICENSE in the repository root for full details.
 
 import { type FC, type JSX, type Ref, useMemo } from "react";
 import classNames from "classnames";
+import { useTranslation } from "react-i18next";
 
 import LogoMark from "../icons/LogoMark.svg?react";
 import LogoType from "../icons/LogoType.svg?react";
 import {
   EndCallButton,
+  MicButton,
+  VideoButton,
   ShareScreenButton,
   SettingsButton,
   ReactionToggleButton,
@@ -20,13 +23,23 @@ import {
   type ReactionData,
 } from "../button";
 import styles from "./CallFooter.module.css";
+import {
+  MediaMuteAndSwitchButton,
+  type MenuOptions,
+} from "./MediaMuteAndSwitchButton";
 import { type Behavior } from "../state/Behavior";
 import { type ViewModel } from "../state/ViewModel";
 import { useBehavior } from "../useBehavior";
 import { type LayoutSwitchViewModel } from "../state/LayoutSwitchViewModel";
 import { LayoutSwitch } from "../room/LayoutSwitch";
-import { type MediaMenuViewModel } from "./MediaMenuViewModel";
-import { MediaMenuButton } from "./MediaMenuButton";
+import { type BackgroundEffectGridItem } from "./BackgroundEffectGrid";
+import { SelfPreview } from "./SelfPreview";
+import { type UnusableReason } from "../tracks/backgroundImages";
+import { type LocalVideoMediaTrack } from "@element-hq/matrixrtc-sdk";
+
+export interface BackgroundImageRefusal {
+  reason: UnusableReason | "not-kept";
+}
 
 export interface AudioOutputSwitcher {
   targetOutput: string;
@@ -48,6 +61,16 @@ export interface AudioOutputSwitcher {
  */
 export type FooterSnapshot = FooterActions & FooterState;
 export interface FooterActions {
+  /** Also controls if the audioMute button is disabled */
+  toggleAudio: (() => void) | undefined;
+  /** Also controls if the videoMute button is disabled */
+  toggleVideo: (() => void) | undefined;
+  /** Undefined where background effects can't be chosen. */
+  selectBackgroundEffect: ((id: string) => void) | undefined;
+  /** Undefined where no background can be added. */
+  addBackgroundImage: ((file: File) => void) | undefined;
+  /** Removes an added background by its option id; never the one in force. */
+  removeBackgroundEffect: ((id: string) => void) | undefined;
   toggleScreenSharing: (() => void) | undefined;
   /** Also controls if the settings button is visible */
   openSettings: (() => void) | undefined;
@@ -57,8 +80,22 @@ export interface FooterActions {
 
 // we do not use any ? optional properties so that the vm type is including all fields.
 export interface FooterState {
-  audioMenuVm: MediaMenuViewModel;
-  cameraMenuVm: MediaMenuViewModel;
+  audioEnabled: boolean;
+  audioBusy: boolean;
+  videoEnabled: boolean;
+  videoBusy: boolean;
+  /** The background effect in force, as its option id. */
+  backgroundEffect: string;
+  /** Every effect on offer, in the order they are shown. */
+  backgroundEffects: BackgroundEffectGridItem[];
+  /** What the user is told about effects here, if anything. */
+  backgroundEffectNotice: "unavailable" | "slow" | undefined;
+  /** Whether the first effect chosen is still being prepared. */
+  backgroundEffectSettling: boolean;
+  /** Why the last file offered couldn't be kept, if it couldn't. */
+  backgroundImageRefusal: BackgroundImageRefusal | undefined;
+  /** The camera to preview, with the effect in force; null while it is off. */
+  cameraTrack: LocalVideoMediaTrack | null;
   showFooter: boolean;
 
   /* This is needed for WindowMode = "flat" */
@@ -85,6 +122,19 @@ export interface FooterState {
   // debug stuff
   debugTileLayout: boolean;
   tileStoreGeneration: number | undefined;
+
+  /** Providing no options `[]` or `undefined` will imply that we dont have a audio fast switcher */
+  audioOptions: MenuOptions[];
+  /** Output (speaker) devices. */
+  audioOutputOptions: MenuOptions[];
+  /** Providing no options `[]` or `undefined` will imply that we dont have a audio fast switcher */
+  videoOptions: MenuOptions[];
+  selectedAudio: string | undefined;
+  selectedAudioOutput: string | undefined;
+  selectedVideo: string | undefined;
+  selectAudioButtonOption: ((deviceId: string) => void) | undefined;
+  selectAudioOutputOption: ((deviceId: string) => void) | undefined;
+  selectVideoButtonOption: ((option: string) => void) | undefined;
 }
 
 export interface FooterProps {
@@ -100,14 +150,19 @@ export const CallFooter: FC<FooterProps> = ({
   children,
   vm,
 }) => {
+  const { t } = useTranslation();
   const asOverlay = useBehavior(vm.asOverlay$);
   const showFooter = useBehavior(vm.showFooter$);
   const hideControls = useBehavior(vm.hideControls$);
   const showModals = useBehavior(vm.showModals$);
   const layoutSwitchVm = useBehavior(vm.layoutSwitchVm$);
-  const audioMenuVm = useBehavior(vm.audioMenuVm$);
-  const cameraMenuVm = useBehavior(vm.cameraMenuVm$);
   const openSettings = useBehavior(vm.openSettings$);
+  const audioEnabled = useBehavior(vm.audioEnabled$);
+  const audioBusy = useBehavior(vm.audioBusy$);
+  const videoEnabled = useBehavior(vm.videoEnabled$);
+  const videoBusy = useBehavior(vm.videoBusy$);
+  const toggleAudio = useBehavior(vm.toggleAudio$);
+  const toggleVideo = useBehavior(vm.toggleVideo$);
   const sharingScreen = useBehavior(vm.sharingScreen$);
   const toggleScreenSharing = useBehavior(vm.toggleScreenSharing$);
   const reactionIdentifier = useBehavior(vm.reactionIdentifier$);
@@ -115,6 +170,38 @@ export const CallFooter: FC<FooterProps> = ({
   const audioOutputSwitcher = useBehavior(vm.audioOutputSwitcher$);
   const hangup = useBehavior(vm.hangup$);
   const debugTileLayout = useBehavior(vm.debugTileLayout$);
+  const videoOptions = useBehavior(vm.videoOptions$);
+  const selectedVideo = useBehavior(vm.selectedVideo$);
+  const audioOptions = useBehavior(vm.audioOptions$);
+  const selectedAudio = useBehavior(vm.selectedAudio$);
+  const selectAudioButtonOption = useBehavior(vm.selectAudioButtonOption$);
+  const audioOutputOptions = useBehavior(vm.audioOutputOptions$);
+  const selectedAudioOutput = useBehavior(vm.selectedAudioOutput$);
+  const selectAudioOutputOption = useBehavior(vm.selectAudioOutputOption$);
+  const selectVideoButtonOption = useBehavior(vm.selectVideoButtonOption$);
+  const backgroundEffect = useBehavior(vm.backgroundEffect$);
+  const selectBackgroundEffect = useBehavior(vm.selectBackgroundEffect$);
+  const backgroundEffectNotice = useBehavior(vm.backgroundEffectNotice$);
+  const backgroundEffectSettling = useBehavior(vm.backgroundEffectSettling$);
+  const addBackgroundImage = useBehavior(vm.addBackgroundImage$);
+  const removeBackgroundEffect = useBehavior(vm.removeBackgroundEffect$);
+  const cameraTrack = useBehavior(vm.cameraTrack$);
+  const refusal = useBehavior(vm.backgroundImageRefusal$);
+  const refusalMessage = useMemo(() => {
+    switch (refusal?.reason) {
+      case undefined:
+        return undefined;
+      case "not-an-image":
+        return { text: t("error.background_not_an_image") };
+      case "animated":
+        return { text: t("error.background_animated") };
+      case "undecodable":
+        return { text: t("error.background_undecodable") };
+      case "not-kept":
+        return { text: t("error.background_not_kept") };
+    }
+  }, [refusal, t]);
+  const backgroundEffects = useBehavior(vm.backgroundEffects$);
   const buttonSize = useBehavior(vm.buttonSize$);
   const showLogo = useBehavior(vm.showLogo$);
 
@@ -134,20 +221,78 @@ export const CallFooter: FC<FooterProps> = ({
     );
   }
 
-  buttons.push(
-    <MediaMenuButton
-      key="audio"
-      kind="audio"
-      vm={audioMenuVm}
-      size={buttonSize}
-    />,
-    <MediaMenuButton
-      key="video"
-      kind="video"
-      vm={cameraMenuVm}
-      size={buttonSize}
-    />,
-  );
+  if ((audioOptions?.length ?? 0) > 0) {
+    buttons.push(
+      <MediaMuteAndSwitchButton
+        key="audio"
+        iconsAndLabels="audio"
+        enabled={audioEnabled ?? false}
+        busy={audioBusy ?? false}
+        onMuteClick={toggleAudio}
+        data-testid="incall_mute"
+        options={audioOptions}
+        selectedOption={selectedAudio}
+        onSelect={selectAudioButtonOption}
+        outputOptions={audioOutputOptions}
+        selectedOutputOption={selectedAudioOutput}
+        onSelectOutput={selectAudioOutputOption}
+      />,
+    );
+  } else {
+    buttons.push(
+      <MicButton
+        size={buttonSize}
+        key="audio"
+        enabled={audioEnabled ?? false}
+        busy={audioBusy ?? false}
+        onClick={toggleAudio}
+        disabled={(audioBusy ?? false) || toggleAudio === undefined}
+        data-testid="incall_mute"
+      />,
+    );
+  }
+
+  if ((videoOptions?.length ?? 0) > 0) {
+    buttons.push(
+      <MediaMuteAndSwitchButton
+        key="video"
+        iconsAndLabels="video"
+        enabled={videoEnabled ?? false}
+        busy={videoBusy ?? false}
+        onMuteClick={toggleVideo}
+        options={videoOptions}
+        selectedOption={selectedVideo}
+        onSelect={selectVideoButtonOption}
+        backgroundEffects={backgroundEffects}
+        selectedBackgroundEffect={backgroundEffect}
+        onSelectBackgroundEffect={selectBackgroundEffect}
+        backgroundEffectSettling={backgroundEffectSettling}
+        onAddBackgroundImage={addBackgroundImage}
+        onRemoveBackgroundEffect={removeBackgroundEffect}
+        selfPreview={<SelfPreview track={cameraTrack} />}
+        backgroundImageRefusal={refusalMessage}
+        backgroundEffectNotice={
+          backgroundEffectNotice === "unavailable"
+            ? t("background_effects.unavailable")
+            : backgroundEffectNotice === "slow"
+              ? t("background_effects.slow")
+              : undefined
+        }
+      />,
+    );
+  } else {
+    buttons.push(
+      <VideoButton
+        size={buttonSize}
+        key="video"
+        enabled={videoEnabled ?? false}
+        busy={videoBusy ?? false}
+        onClick={toggleVideo}
+        disabled={(videoBusy ?? false) || toggleVideo === undefined}
+        data-testid="incall_videomute"
+      />,
+    );
+  }
 
   if (toggleScreenSharing !== undefined) {
     buttons.push(

src/components/CallFooterViewModel.test.ts

@@ -5,15 +5,18 @@ SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
 Please see LICENSE in the repository root for full details.
 */
 
-import { describe, expect, it, vi } from "vitest";
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { BehaviorSubject } from "rxjs";
+import { type LocalVideoMediaTrack } from "@element-hq/matrixrtc-sdk";
 
 import {
+  flushPromises,
   testScope,
   mockMuteStates,
   mockMediaDevices,
   mockVideoTrack,
 } from "../utils/test";
-import { constant } from "../state/Behavior";
+import { type Behavior, constant } from "../state/Behavior";
 import { type BackgroundEffectsState } from "../state/BackgroundEffects";
 import type { CallViewModel } from "../state/CallViewModel/CallViewModel";
 import type { Layout } from "../state/layout-types";
@@ -24,6 +27,15 @@ import {
   createLobbyFooterViewModel,
 } from "./CallFooterViewModel";
 import { HeaderStyle } from "../UrlParams";
+import { backgroundEffect as backgroundEffectSetting } from "../settings/settings";
+import { shippedBackgrounds } from "../tracks/backgroundEffectCatalog";
+import type * as BackgroundImages from "../tracks/backgroundImages";
+import {
+  type AddedBackground,
+  addedBackgrounds,
+  maxAddedBackgrounds,
+  UnusableImage,
+} from "../tracks/backgroundImages";
 
 const platformMock = vi.hoisted(() => vi.fn(() => "desktop"));
 vi.mock("../Platform", () => ({
@@ -32,6 +44,35 @@ vi.mock("../Platform", () => ({
   },
 }));
 
+// The SDK's own check needs WebGL and canvas APIs jsdom does not have.
+const sdkSupportMock = vi.hoisted(() => vi.fn(() => false));
+const modernRouteMock = vi.hoisted(() => vi.fn(() => true));
+vi.mock("@livekit/track-processors", () => ({
+  supportsBackgroundProcessors: (): boolean => sdkSupportMock(),
+  supportsModernBackgroundProcessors: (): boolean => modernRouteMock(),
+}));
+
+const store = vi.hoisted(() => ({
+  add: vi.fn<(file: Blob) => Promise<string>>(),
+  remove: vi.fn<(id: string) => Promise<void>>(),
+}));
+vi.mock("../tracks/backgroundImages", async (original) => {
+  const { BehaviorSubject } = await import("rxjs");
+  return {
+    ...(await original<typeof BackgroundImages>()),
+    addedBackgrounds: {
+      added$: new BehaviorSubject<AddedBackground[] | undefined>([]),
+      add: store.add,
+      remove: store.remove,
+    },
+  };
+});
+
+const outputSelectionMock = vi.hoisted(() => vi.fn(() => true));
+vi.mock("livekit-client", () => ({
+  supportsAudioOutputSelection: (): boolean => outputSelectionMock(),
+}));
+
 /**
  * Returns the minimum set of CallViewModel fields required by
  * createCallFooterViewModel, with all other properties stubbed to
@@ -72,82 +113,424 @@ const pipLayout: Layout = {
   spotlight: {} as SpotlightTileViewModel,
 };
 
-const pipeline = constant<BackgroundEffectsState>({
-  supported: true,
+const noPipeline = constant<BackgroundEffectsState>({
+  supported: false,
   processor: undefined,
 });
 
-const oneOfEach = {
-  available$: constant(
-    new Map<string, DeviceLabel>([["1", { type: "number", number: 1 }]]),
-  ),
-  selected$: constant(undefined),
-  select: vi.fn(),
-};
-const devices = mockMediaDevices({
-  audioInput: oneOfEach,
-  videoInput: oneOfEach,
+/** The provider's verdict, which the SDK's check stands for here. */
+function pipelineAsTheSdkSays(): Behavior<BackgroundEffectsState> {
+  return constant({ supported: sdkSupportMock(), processor: undefined });
+}
+
+const twoMicsAndOneCamMediaDevices = mockMediaDevices({
+  audioInput: {
+    available$: constant(
+      new Map<string, DeviceLabel>([
+        ["mic1", { type: "number", number: 1 }],
+        ["mic2", { type: "name", name: "Microphone 2" }],
+      ]),
+    ),
+    selected$: constant(undefined),
+    select: vi.fn(),
+  },
+  videoInput: {
+    available$: constant(
+      new Map<string, DeviceLabel>([
+        ["cam1", { type: "name", name: "Camera 1" }],
+      ]),
+    ),
+    selected$: constant(undefined),
+    select: vi.fn(),
+  },
 });
 
 describe("createCallFooterViewModel", () => {
-  it.each([
-    ["desktop", "grid", true, gridLayout],
-    ["ios", "grid", false, gridLayout],
-    ["desktop", "pip", false, pipLayout],
-  ] as const)(
-    "on %s in a %s layout, offers the device menus: %s",
-    (platform, _, offered, layout) => {
+  describe("selectAudioOutputOption", () => {
+    function buildFooterVm(): ReturnType<typeof createCallFooterViewModel> {
+      platformMock.mockReturnValue("desktop");
+      return createCallFooterViewModel(
+        testScope(),
+        buildMinimalCallViewModel(gridLayout),
+        mockMuteStates(),
+        twoMicsAndOneCamMediaDevices,
+        noPipeline,
+        /* reactionIdentifier */ undefined,
+        { showControls: true, header: HeaderStyle.Standard },
+      );
+    }
+
+    it("is withheld where the platform cannot route audio to a chosen device", () => {
+      outputSelectionMock.mockReturnValue(false);
+      expect(buildFooterVm().selectAudioOutputOption$.value).toBeUndefined();
+    });
+
+    it("is offered where the platform can route audio to a chosen device", () => {
+      outputSelectionMock.mockReturnValue(true);
+      expect(buildFooterVm().selectAudioOutputOption$.value).toBeDefined();
+    });
+  });
+
+  describe("audioOutputOptions", () => {
+    it("is an empty list, not absent, where the platform enumerates no outputs", () => {
+      platformMock.mockReturnValue("desktop");
+      outputSelectionMock.mockReturnValue(true);
+
+      const vm = createCallFooterViewModel(
+        testScope(),
+        buildMinimalCallViewModel(gridLayout),
+        mockMuteStates(),
+        mockMediaDevices({
+          audioInput: {
+            available$: constant(
+              new Map<string, DeviceLabel>([
+                ["mic1", { type: "name", name: "Microphone 1" }],
+              ]),
+            ),
+            selected$: constant(undefined),
+            select: vi.fn(),
+          },
+          // As Safari: no outputs listed.
+          audioOutput: {
+            available$: constant(new Map<string, DeviceLabel>()),
+            selected$: constant(undefined),
+            select: vi.fn(),
+          },
+        }),
+        noPipeline,
+        /* reactionIdentifier */ undefined,
+        { showControls: true, header: HeaderStyle.Standard },
+      );
+
+      // Empty, not undefined: undefined would hide the section.
+      expect(vm.audioOutputOptions$.value).toEqual([]);
+    });
+  });
+
+  describe("audioOptions and videoOptions", () => {
+    function checkEmptyFor(platform: string, layout: Layout): void {
       platformMock.mockReturnValue(platform);
+
       const vm = createCallFooterViewModel(
         testScope(),
         buildMinimalCallViewModel(layout),
         mockMuteStates(),
-        devices,
-        pipeline,
+        twoMicsAndOneCamMediaDevices,
+        noPipeline,
         /* reactionIdentifier */ undefined,
         { showControls: true, header: HeaderStyle.Standard },
       );
-      const audio = vm.audioMenuVm$.value;
-      const camera = vm.cameraMenuVm$.value;
-      expect(audio.options$.value.length > 0).toBe(offered);
-      expect(camera.options$.value.length > 0).toBe(offered);
-      expect(camera.selectBackgroundEffect$.value !== undefined).toBe(offered);
-    },
-  );
 
-  it("previews the call's camera", () => {
-    const track = mockVideoTrack({});
-    const vm = createCallFooterViewModel(
-      testScope(),
-      { ...buildMinimalCallViewModel(gridLayout), camera$: constant(track) },
-      mockMuteStates(),
-      devices,
-      pipeline,
-      /* reactionIdentifier */ undefined,
-      { showControls: true, header: HeaderStyle.Standard },
-    );
-    expect(vm.cameraMenuVm$.value.cameraTrack$.value).toBe(track);
+      expect(vm.audioOptions$.value).toEqual([]);
+      expect(vm.videoOptions$.value).toEqual([]);
+    }
+    it("are both empty when the platform is iOS", () => {
+      checkEmptyFor("ios", gridLayout);
+    });
+    it("are both empty when the layout is pip", () => {
+      checkEmptyFor("desktop", pipLayout);
+    });
+
+    it("are populated when the platform is desktop and the layout is not PiP", () => {
+      platformMock.mockReturnValue("desktop");
+
+      const vm = createCallFooterViewModel(
+        testScope(),
+        buildMinimalCallViewModel(gridLayout),
+        mockMuteStates(),
+        twoMicsAndOneCamMediaDevices,
+        noPipeline,
+        /* reactionIdentifier */ undefined,
+        { showControls: true, header: HeaderStyle.Standard },
+      );
+
+      expect(vm.audioOptions$?.value).toEqual([
+        {
+          id: "mic1",
+          label: {
+            number: 1,
+            type: "number",
+          },
+        },
+        {
+          id: "mic2",
+          label: {
+            name: "Microphone 2",
+            type: "name",
+          },
+        },
+      ]);
+      expect(vm.videoOptions$?.value).toEqual([
+        {
+          id: "cam1",
+          label: {
+            name: "Camera 1",
+            type: "name",
+          },
+        },
+      ]);
+    });
   });
-});
-
-describe("createLobbyFooterViewModel", () => {
-  it("offers the device menus even on a phone, previewing the lobby's camera", () => {
-    platformMock.mockReturnValue("ios");
-    const track = mockVideoTrack({});
-    const vm = createLobbyFooterViewModel(
-      testScope(),
-      mockMuteStates(),
-      devices,
-      pipeline,
-      constant(track),
-      /* openSettings */ undefined,
-      /* hangup */ undefined,
-      /* showLogo */ false,
-    );
-    const camera = vm.cameraMenuVm$.value;
-    expect(vm.audioMenuVm$.value.options$.value).not.toEqual([]);
-    expect(camera.options$.value).not.toEqual([]);
-    expect(camera.selectBackgroundEffect$.value).toBeDefined();
-    expect(camera.cameraTrack$.value).toBe(track);
+
+  describe("background effects", () => {
+    afterEach(() => backgroundEffectSetting.setValue("none"));
+
+    // The lobby, because in a call the whole device switcher is already
+    // withheld on a phone, whatever the verdict says.
+    function lobbyOn(
+      platform: string,
+    ): ReturnType<typeof createLobbyFooterViewModel> {
+      platformMock.mockReturnValue(platform);
+      return createLobbyFooterViewModel(
+        testScope(),
+        mockMuteStates(),
+        twoMicsAndOneCamMediaDevices,
+        pipelineAsTheSdkSays(),
+        /* camera$ */ constant(null),
+        /* openSettings */ undefined,
+        /* hangup */ undefined,
+        /* showLogo */ false,
+      );
+    }
+
+    it("offers them on a phone whose browser can run them", () => {
+      sdkSupportMock.mockReturnValue(true);
+      expect(lobbyOn("ios").selectBackgroundEffect$.value).toBeDefined();
+    });
+
+    it("offers them on a desktop whose browser can run them", () => {
+      sdkSupportMock.mockReturnValue(true);
+      expect(lobbyOn("desktop").selectBackgroundEffect$.value).toBeDefined();
+    });
+
+    it("offers nothing where the browser itself cannot run them", () => {
+      sdkSupportMock.mockReturnValue(false);
+      expect(lobbyOn("desktop").selectBackgroundEffect$.value).toBeUndefined();
+      expect(lobbyOn("desktop").addBackgroundImage$.value).toBeUndefined();
+    });
+
+    it("puts no effect in force where the browser cannot run them", () => {
+      backgroundEffectSetting.setValue("blur");
+      sdkSupportMock.mockReturnValue(false);
+      expect(lobbyOn("desktop").backgroundEffect$.value).toBe("none");
+      sdkSupportMock.mockReturnValue(true);
+      expect(lobbyOn("desktop").backgroundEffect$.value).toBe("blur");
+    });
+
+    it("stores the effect chosen", () => {
+      sdkSupportMock.mockReturnValue(true);
+      const vm = lobbyOn("desktop");
+      vm.selectBackgroundEffect$.value?.("image:arc");
+      expect(vm.backgroundEffect$.value).toBe("image:arc");
+      // What isn't an effect on offer is stored as none.
+      vm.selectBackgroundEffect$.value?.("image:gone");
+      expect(backgroundEffectSetting.getValue()).toBe("none");
+    });
+
+    it("says they run slowly where only the slower route exists", () => {
+      sdkSupportMock.mockReturnValue(true);
+      modernRouteMock.mockReturnValue(false);
+      const slow = lobbyOn("desktop");
+      expect(slow.backgroundEffectNotice$.value).toBe("slow");
+      expect(slow.selectBackgroundEffect$.value).toBeDefined();
+      modernRouteMock.mockReturnValue(true);
+      expect(lobbyOn("desktop").backgroundEffectNotice$.value).toBeUndefined();
+    });
+
+    it("offers every effect in order, the added ones removable", () => {
+      sdkSupportMock.mockReturnValue(true);
+      const added$ = addedBackgrounds.added$ as BehaviorSubject<
+        AddedBackground[] | undefined
+      >;
+      added$.next([{ id: "mine", url: "blob:mine" }]);
+      expect(lobbyOn("desktop").backgroundEffects$.value).toEqual([
+        { id: "none", kind: "none", removable: false },
+        { id: "blur", kind: "blur", removable: false },
+        ...shippedBackgrounds.map((background) => ({
+          id: `image:${background.id}`,
+          kind: "image",
+          imageUrl: background.imagePath,
+          removable: false,
+        })),
+        {
+          id: "added:mine",
+          kind: "image",
+          imageUrl: "blob:mine",
+          removable: true,
+        },
+      ]);
+      added$.next([]);
+    });
+
+    it("says they are unavailable where they cannot be chosen", () => {
+      sdkSupportMock.mockReturnValue(false);
+      expect(lobbyOn("desktop").backgroundEffectNotice$.value).toBe(
+        "unavailable",
+      );
+    });
+
+    it("passes on the wait for the first effect", () => {
+      platformMock.mockReturnValue("desktop");
+      const pipeline$ = new BehaviorSubject<BackgroundEffectsState>({
+        supported: true,
+        processor: undefined,
+        wait: "settling",
+      });
+      const vm = createLobbyFooterViewModel(
+        testScope(),
+        mockMuteStates(),
+        twoMicsAndOneCamMediaDevices,
+        pipeline$,
+        /* camera$ */ constant(null),
+        /* openSettings */ undefined,
+        /* hangup */ undefined,
+        /* showLogo */ false,
+      );
+      expect(vm.backgroundEffectSettling$.value).toBe(true);
+      pipeline$.next({ ...pipeline$.value, wait: undefined });
+      expect(vm.backgroundEffectSettling$.value).toBe(false);
+    });
+
+    it("offers nothing once the pipeline fails to build, keeping the choice", () => {
+      platformMock.mockReturnValue("desktop");
+      backgroundEffectSetting.setValue("blur");
+      const pipeline$ = new BehaviorSubject<BackgroundEffectsState>({
+        supported: true,
+        processor: undefined,
+      });
+      const vm = createLobbyFooterViewModel(
+        testScope(),
+        mockMuteStates(),
+        twoMicsAndOneCamMediaDevices,
+        pipeline$,
+        /* camera$ */ constant(null),
+        /* openSettings */ undefined,
+        /* hangup */ undefined,
+        /* showLogo */ false,
+      );
+      expect(vm.backgroundEffect$.value).toBe("blur");
+
+      pipeline$.next({ supported: false, processor: undefined });
+      expect(vm.selectBackgroundEffect$.value).toBeUndefined();
+      expect(vm.addBackgroundImage$.value).toBeUndefined();
+      expect(vm.backgroundEffect$.value).toBe("none");
+      expect(backgroundEffectSetting.getValue()).toBe("blur");
+    });
+
+    it("adding is unavailable at the limit", () => {
+      sdkSupportMock.mockReturnValue(true);
+      const added$ = addedBackgrounds.added$ as BehaviorSubject<
+        AddedBackground[] | undefined
+      >;
+      const vm = lobbyOn("desktop");
+      expect(vm.addBackgroundImage$.value).toBeDefined();
+      added$.next(
+        Array.from({ length: maxAddedBackgrounds }, (_, i) => ({
+          id: `${i}`,
+          url: `blob:${i}`,
+        })),
+      );
+      expect(vm.addBackgroundImage$.value).toBeUndefined();
+      added$.next(added$.value!.slice(1));
+      expect(vm.addBackgroundImage$.value).toBeDefined();
+      added$.next([]);
+    });
+
+    it("says why each refused file was refused", async () => {
+      sdkSupportMock.mockReturnValue(true);
+      const vm = lobbyOn("desktop");
+      store.add.mockRejectedValue(new UnusableImage("animated"));
+      vm.addBackgroundImage$.value!(new File(["x"], "a.gif"));
+      await flushPromises();
+      const first = vm.backgroundImageRefusal$.value;
+      expect(first).toEqual({ reason: "animated" });
+
+      // The same again is a refusal of its own, so it is shown again.
+      vm.addBackgroundImage$.value!(new File(["x"], "a.gif"));
+      await flushPromises();
+      expect(vm.backgroundImageRefusal$.value).toEqual({ reason: "animated" });
+      expect(vm.backgroundImageRefusal$.value).not.toBe(first);
+
+      store.add.mockRejectedValue(new Error("quota"));
+      vm.addBackgroundImage$.value!(new File(["x"], "b.png"));
+      await flushPromises();
+      expect(vm.backgroundImageRefusal$.value).toEqual({ reason: "not-kept" });
+
+      store.add.mockResolvedValue("kept");
+      vm.addBackgroundImage$.value!(new File(["x"], "c.png"));
+      await flushPromises();
+      expect(vm.backgroundImageRefusal$.value).toBeUndefined();
+    });
+
+    it("never removes the background in force", () => {
+      sdkSupportMock.mockReturnValue(true);
+      store.remove.mockResolvedValue();
+      const vm = lobbyOn("desktop");
+      backgroundEffectSetting.setValue("added:worn");
+      vm.removeBackgroundEffect$.value!("added:worn");
+      expect(store.remove).not.toHaveBeenCalled();
+      vm.removeBackgroundEffect$.value!("added:spare");
+      expect(store.remove).toHaveBeenCalledWith("spare");
+    });
+
+    it("previews the lobby's camera while there is one", () => {
+      const track = mockVideoTrack({});
+      const camera$ = new BehaviorSubject<LocalVideoMediaTrack | null>(track);
+      const vm = createLobbyFooterViewModel(
+        testScope(),
+        mockMuteStates(),
+        twoMicsAndOneCamMediaDevices,
+        noPipeline,
+        camera$,
+        /* openSettings */ undefined,
+        /* hangup */ undefined,
+        /* showLogo */ false,
+      );
+      expect(vm.cameraTrack$.value).toBe(track);
+      // The lobby releases the camera when it is turned off
+      camera$.next(null);
+      expect(vm.cameraTrack$.value).toBeNull();
+    });
+
+    it("previews the call's camera only while it is not muted", () => {
+      const muted$ = new BehaviorSubject(false);
+      const track = mockVideoTrack({ muted$ });
+      const vm = createCallFooterViewModel(
+        testScope(),
+        { ...buildMinimalCallViewModel(gridLayout), camera$: constant(track) },
+        mockMuteStates(),
+        twoMicsAndOneCamMediaDevices,
+        noPipeline,
+        /* reactionIdentifier */ undefined,
+        { showControls: true, header: HeaderStyle.Standard },
+      );
+      expect(vm.cameraTrack$.value).toBe(track);
+      muted$.next(true);
+      expect(vm.cameraTrack$.value).toBeNull();
+      muted$.next(false);
+      expect(vm.cameraTrack$.value).toBe(track);
+    });
+
+    it("availability is the same before and during a call", () => {
+      for (const supported of [true, false]) {
+        sdkSupportMock.mockReturnValue(supported);
+        const lobby = lobbyOn("desktop");
+        const inCall = createCallFooterViewModel(
+          testScope(),
+          buildMinimalCallViewModel(gridLayout),
+          mockMuteStates(),
+          twoMicsAndOneCamMediaDevices,
+          pipelineAsTheSdkSays(),
+          /* reactionIdentifier */ undefined,
+          { showControls: true, header: HeaderStyle.Standard },
+        );
+        const offeredInLobby =
+          lobby.selectBackgroundEffect$.value !== undefined;
+        expect(inCall.selectBackgroundEffect$.value !== undefined).toBe(
+          offeredInLobby,
+        );
+        expect(offeredInLobby).toBe(supported);
+      }
+    });
   });
 });

src/components/CallFooterViewModel.tsx

@@ -5,24 +5,253 @@ SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
 Please see LICENSE in the repository root for full details.
 */
 
-import { combineLatest, map, type Observable } from "rxjs";
+import {
+  BehaviorSubject,
+  combineLatest,
+  distinctUntilChanged,
+  map,
+  type Observable,
+  of,
+  switchMap,
+} from "rxjs";
+import { supportsAudioOutputSelection } from "livekit-client";
 import { type LocalVideoMediaTrack } from "@element-hq/matrixrtc-sdk";
+import { supportsModernBackgroundProcessors } from "@livekit/track-processors";
+import { logger } from "matrix-js-sdk/lib/logger";
+
+import {
+  parseEffect,
+  serializeEffect,
+  shippedBackgrounds,
+} from "../tracks/backgroundEffectCatalog";
+import {
+  type AddedBackground,
+  addedBackgrounds,
+  maxAddedBackgrounds,
+  UnusableImage,
+} from "../tracks/backgroundImages";
 
 import { type CallViewModel } from "../state/CallViewModel/CallViewModel";
 import { type BackgroundEffectsState } from "../state/BackgroundEffects";
+import { type MenuOptions } from "./MediaMuteAndSwitchButton";
 import { type MediaDevices } from "../state/MediaDevices";
-import { debugTileLayout as debugTileLayoutSetting } from "../settings/settings";
+import {
+  backgroundEffect as backgroundEffectSetting,
+  debugTileLayout as debugTileLayoutSetting,
+} from "../settings/settings";
 import { type Behavior, constant } from "../state/Behavior";
 import type { ObservableScope } from "../state/ObservableScope";
 import { type MuteStates } from "../state/MuteStates";
 import { createStaticViewModel, type ViewModel } from "../state/ViewModel";
 import { HeaderStyle } from "../UrlParams";
 import { platform } from "../Platform";
-import { type FooterSnapshot } from "./CallFooter";
-import {
-  createAudioMenuViewModel,
-  createCameraMenuViewModel,
-} from "./MediaMenuViewModel";
+import { type BackgroundImageRefusal, type FooterSnapshot } from "./CallFooter";
+import { type BackgroundEffectGridItem } from "./BackgroundEffectGrid";
+
+/**
+ * Shared helper: maps MuteStates into the audio/video enabled + toggle behaviors
+ * needed by FooterSnapshot.
+ */
+function buildMuteBehaviors(
+  scope: ObservableScope,
+  muteStates: MuteStates,
+): Pick<
+  ViewModel<FooterSnapshot>,
+  | "audioEnabled$"
+  | "audioBusy$"
+  | "toggleAudio$"
+  | "videoEnabled$"
+  | "videoBusy$"
+  | "toggleVideo$"
+> {
+  return {
+    audioEnabled$: muteStates.audio.enabled$,
+    audioBusy$: muteStates.audio.syncing$,
+    toggleAudio$: scope.behavior(
+      muteStates.audio.toggle$.pipe(map((t) => t ?? undefined)),
+    ),
+    videoEnabled$: muteStates.video.enabled$,
+    videoBusy$: muteStates.video.syncing$,
+    toggleVideo$: scope.behavior(
+      muteStates.video.toggle$.pipe(map((t) => t ?? undefined)),
+    ),
+  };
+}
+
+/**
+ * Shared helper: maps MediaDevices into the audio/video device-list behaviors
+ * needed by FooterSnapshot (options, selection, callbacks, background effect).
+ */
+function buildDeviceBehaviors(
+  scope: ObservableScope,
+  mediaDevices: MediaDevices,
+  /** return empty arrays for  audioOptions and videoOptions*/
+  disableSwitcher$: Behavior<boolean>,
+  backgroundEffectsState$: Observable<BackgroundEffectsState>,
+  /** The camera as the pipeline has it, for the menu's preview. */
+  camera$: Observable<LocalVideoMediaTrack | null | undefined>,
+): Pick<
+  ViewModel<FooterSnapshot>,
+  | "audioOptions$"
+  | "selectedAudio$"
+  | "selectAudioButtonOption$"
+  | "audioOutputOptions$"
+  | "selectedAudioOutput$"
+  | "selectAudioOutputOption$"
+  | "videoOptions$"
+  | "selectedVideo$"
+  | "selectVideoButtonOption$"
+  | "backgroundEffect$"
+  | "selectBackgroundEffect$"
+  | "backgroundEffects$"
+  | "backgroundEffectNotice$"
+  | "backgroundEffectSettling$"
+  | "addBackgroundImage$"
+  | "backgroundImageRefusal$"
+  | "removeBackgroundEffect$"
+  | "cameraTrack$"
+> {
+  const options$ = (
+    available$: Behavior<Map<string, MenuOptions["label"]>>,
+  ): Observable<MenuOptions[]> =>
+    disableSwitcher$.pipe(
+      switchMap((disable) =>
+        disable
+          ? constant([] as MenuOptions[])
+          : available$.pipe(
+              map((available) =>
+                [...available.entries()].map(([id, label]) => ({ id, label })),
+              ),
+            ),
+      ),
+    );
+
+  // Also false once the pipeline has failed to build this session.
+  const supported$ = backgroundEffectsState$.pipe(
+    map(({ supported }) => supported === true),
+    distinctUntilChanged(),
+  );
+  const slow = !supportsModernBackgroundProcessors();
+  const offered$ = combineLatest([disableSwitcher$, supported$]).pipe(
+    map(([switcherDisabled, supported]) => !switcherDisabled && supported),
+  );
+  // A new object for each refusal, so the same one twice is shown twice.
+  const refusal$ = new BehaviorSubject<BackgroundImageRefusal | undefined>(
+    undefined,
+  );
+  return {
+    audioOptions$: scope.behavior(options$(mediaDevices.audioInput.available$)),
+    selectedAudio$: scope.behavior(
+      mediaDevices.audioInput.selected$.pipe(map((s) => s?.id)),
+    ),
+    selectAudioButtonOption$: constant(mediaDevices.audioInput.select),
+    audioOutputOptions$: scope.behavior(
+      options$(mediaDevices.audioOutput.available$),
+    ),
+    selectedAudioOutput$: scope.behavior(
+      mediaDevices.audioOutput.selected$.pipe(map((s) => s?.id)),
+    ),
+    // Withheld where the platform can't route audio to a chosen device, which
+    // disables the speaker section.
+    selectAudioOutputOption$: constant(
+      supportsAudioOutputSelection()
+        ? mediaDevices.audioOutput.select
+        : undefined,
+    ),
+    videoOptions$: scope.behavior(options$(mediaDevices.videoInput.available$)),
+    selectedVideo$: scope.behavior(
+      mediaDevices.videoInput.selected$.pipe(map((s) => s?.id)),
+    ),
+    selectVideoButtonOption$: constant(mediaDevices.videoInput.select),
+    backgroundEffect$: scope.behavior(
+      combineLatest([backgroundEffectSetting.value$, supported$]).pipe(
+        map(([raw, supported]) =>
+          supported ? serializeEffect(parseEffect(raw)) : "none",
+        ),
+      ),
+    ),
+    selectBackgroundEffect$: scope.behavior(
+      offered$.pipe(
+        map((offered) =>
+          offered
+            ? (id: string): void =>
+                backgroundEffectSetting.setValue(
+                  serializeEffect(parseEffect(id)),
+                )
+            : undefined,
+        ),
+      ),
+    ),
+    backgroundEffects$: scope.behavior(
+      addedBackgrounds.added$.pipe(
+        map((added) => backgroundEffectChoices(added ?? [])),
+      ),
+    ),
+    backgroundEffectNotice$: scope.behavior(
+      offered$.pipe(
+        map((offered) =>
+          !offered ? "unavailable" : slow ? "slow" : undefined,
+        ),
+      ),
+    ),
+    backgroundEffectSettling$: scope.behavior(
+      backgroundEffectsState$.pipe(
+        map(({ wait }) => wait !== undefined),
+        distinctUntilChanged(),
+      ),
+      false,
+    ),
+    // Kept and offered, not put on: that waits for the user to choose it.
+    addBackgroundImage$: scope.behavior(
+      combineLatest([offered$, addedBackgrounds.added$]).pipe(
+        map(([offered, added]) =>
+          offered && (added?.length ?? 0) < maxAddedBackgrounds
+            ? (file: File): void => {
+                refusal$.next(undefined);
+                addedBackgrounds.add(file).catch((e) => {
+                  logger.warn("Could not keep that background", e);
+                  refusal$.next({
+                    reason: e instanceof UnusableImage ? e.reason : "not-kept",
+                  });
+                });
+              }
+            : undefined,
+        ),
+      ),
+    ),
+    backgroundImageRefusal$: refusal$,
+    // None while muted: the call mutes its track rather than releasing it.
+    cameraTrack$: scope.behavior(
+      camera$.pipe(
+        switchMap((camera) =>
+          camera
+            ? camera.muted$.pipe(map((muted) => (muted ? null : camera)))
+            : of(null),
+        ),
+      ),
+      null,
+    ),
+    // Never the one in force: taking it away would leave nothing chosen.
+    removeBackgroundEffect$: scope.behavior(
+      offered$.pipe(
+        map((offered) =>
+          offered
+            ? (optionId: string): void => {
+                const effect = parseEffect(optionId);
+                if (effect.kind !== "added") return;
+                if (backgroundEffectSetting.getValue() === optionId) return;
+                addedBackgrounds
+                  .remove(effect.id)
+                  .catch((e) =>
+                    logger.warn("Could not remove that background", e),
+                  );
+              }
+            : undefined,
+        ),
+      ),
+    ),
+  };
+}
 
 /**
  * Creates the ViewModel for the CallFooter.
@@ -57,23 +286,13 @@ export function createCallFooterViewModel(
     isPip$.pipe(map((isPip) => isPip || platform !== "desktop")),
   );
   return {
-    audioMenuVm$: constant(
-      createAudioMenuViewModel(
-        scope,
-        muteStates,
-        mediaDevices,
-        disableDeviceSwitcher$,
-      ),
-    ),
-    cameraMenuVm$: constant(
-      createCameraMenuViewModel(
-        scope,
-        muteStates,
-        mediaDevices,
-        disableDeviceSwitcher$,
-        backgroundEffectsState$,
-        callModel.camera$,
-      ),
+    ...buildMuteBehaviors(scope, muteStates),
+    ...buildDeviceBehaviors(
+      scope,
+      mediaDevices,
+      disableDeviceSwitcher$,
+      backgroundEffectsState$,
+      callModel.camera$,
     ),
     // candidat to move into the FooterViewModel
     showFooter$: callModel.showFooter$,
@@ -153,40 +372,72 @@ export function createLobbyFooterViewModel(
   hangup: (() => void) | undefined,
   showLogo: boolean,
 ): ViewModel<FooterSnapshot> {
-  return createStaticViewModel({
-    // we can safly skip any props that we do not need.
-    // The view model will then have less keys.
-    // But as soon as we call `useViewModel` and convert back to a snapshot the missing props will
-    // be correcty matching the snapshot type.
-    showLogo,
-    hideControls: false,
-    asOverlay: false,
-    showModals: true,
-    buttonSize: "lg",
-    openSettings,
-    hangup,
-    debugTileLayout: false,
-    showFooter: true,
-    toggleScreenSharing: undefined,
-    layoutSwitchVm: null,
-    sharingScreen: false,
-    audioOutputSwitcher: undefined,
-    reactionIdentifier: undefined,
-    reactionData: undefined,
-    tileStoreGeneration: undefined,
-    audioMenuVm: createAudioMenuViewModel(
+  return {
+    ...createStaticViewModel({
+      // we can safly skip any props that we do not need.
+      // The view model will then have less keys.
+      // But as soon as we call `useViewModel` and convert back to a snapshot the missing props will
+      // be correcty matching the snapshot type.
+      showLogo,
+      hideControls: false,
+      asOverlay: false,
+      showModals: true,
+      buttonSize: "lg",
+      openSettings,
+      hangup,
+      debugTileLayout: false,
+      showFooter: true,
+      toggleAudio: undefined,
+      toggleVideo: undefined,
+      toggleScreenSharing: undefined,
+      audioEnabled: undefined,
+      audioBusy: false,
+      videoEnabled: undefined,
+      videoBusy: false,
+      layoutSwitchVm: null,
+      sharingScreen: false,
+      audioOutputSwitcher: undefined,
+      reactionIdentifier: undefined,
+      reactionData: undefined,
+      tileStoreGeneration: undefined,
+      audioOptions: undefined,
+      audioOutputOptions: undefined,
+      videoOptions: undefined,
+      selectedAudio: undefined,
+      selectedAudioOutput: undefined,
+      selectedVideo: undefined,
+      selectAudioButtonOption: undefined,
+      selectAudioOutputOption: undefined,
+      selectVideoButtonOption: undefined,
+    }),
+    ...buildMuteBehaviors(scope, muteStates),
+    ...buildDeviceBehaviors(
       scope,
-      muteStates,
-      mediaDevices,
-      constant(false),
-    ),
-    cameraMenuVm: createCameraMenuViewModel(
-      scope,
-      muteStates,
       mediaDevices,
       constant(false),
       backgroundEffectsState$,
       camera$,
     ),
-  });
+  };
+}
+
+function backgroundEffectChoices(
+  added: AddedBackground[],
+): BackgroundEffectGridItem[] {
+  return [
+    { id: serializeEffect({ kind: "none" }), kind: "none", removable: false },
+    { id: serializeEffect({ kind: "blur" }), kind: "blur", removable: false },
+    ...shippedBackgrounds.map((background) => ({
+      id: serializeEffect({ kind: "shipped", id: background.id }),
+      kind: "image" as const,
+      imageUrl: background.imagePath,
+      removable: false,
+    })),
+    ...added.map((background) => ({
+      id: serializeEffect({ kind: "added", id: background.id }),
+      kind: "image" as const,
+      imageUrl: background.url,
+      removable: true,
+    })),
+  ];
 }

src/components/MediaMenuButton.stories.tsx

@@ -1,193 +0,0 @@
-/*
-Copyright 2026 Element Creations Ltd.
-
-SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
-Please see LICENSE in the repository root for full details.
-*/
-
-import { expect, fn, userEvent, within } from "storybook/test";
-import { type JSX, type ReactNode } from "react";
-
-import type { Meta, StoryObj } from "@storybook/react-vite";
-import { MediaMenuButton } from "./MediaMenuButton";
-import { type MediaMenuSnapshot } from "./MediaMenuViewModel";
-import { useStaticViewModel } from "../state/ViewModel";
-import { MediaDevicesContext } from "../MediaDevicesContext";
-import { MediaDevices } from "../state/MediaDevices";
-import { globalScope } from "../state/ObservableScope";
-
-const mediaDevices = new MediaDevices(globalScope, {
-  controlledAudioDevices: false,
-});
-
-/** Builds the view model from the story's args, so each field is a control. */
-function MediaMenuButtonStoryWrapper({
-  kind,
-  ...snapshot
-}: MediaMenuSnapshot & { kind: "audio" | "video" }): ReactNode {
-  const vm = useStaticViewModel(snapshot);
-  return <MediaMenuButton kind={kind} vm={vm} size="lg" />;
-}
-
-const meta = {
-  component: MediaMenuButtonStoryWrapper,
-  decorators: [
-    (Story): JSX.Element => (
-      <MediaDevicesContext value={mediaDevices}>
-        <Story />
-      </MediaDevicesContext>
-    ),
-  ],
-} satisfies Meta<typeof MediaMenuButtonStoryWrapper>;
-
-export default meta;
-type Story = StoryObj<typeof meta>;
-
-const empty = {
-  outputOptions: [],
-  selectedOutput: undefined,
-  selectOutput: undefined,
-  backgroundEffect: undefined,
-  backgroundEffects: [],
-  backgroundEffectNotice: undefined,
-  backgroundEffectSettling: false,
-  backgroundImageRefusal: undefined,
-  selectBackgroundEffect: undefined,
-  addBackgroundImage: undefined,
-  removeBackgroundEffect: undefined,
-  cameraTrack: null,
-} satisfies Partial<MediaMenuSnapshot>;
-
-export const Microphone: Story = {
-  args: {
-    ...empty,
-    kind: "audio",
-    enabled: true,
-    busy: false,
-    toggle: fn(),
-    options: [
-      { id: "mic1", label: { type: "name", name: "Microphone 1" } },
-      { id: "mic2", label: { type: "name", name: "Microphone 2" } },
-    ],
-    selected: "mic1",
-    select: fn(),
-    outputOptions: [
-      { id: "default", label: { type: "default", name: "Built-in Output" } },
-    ],
-    selectedOutput: "default",
-    selectOutput: fn(),
-  },
-  play: async ({ args, canvasElement }) => {
-    await userEvent.click(
-      within(canvasElement).getByRole("switch", { name: "Mute microphone" }),
-    );
-    await expect(args.toggle).toHaveBeenCalled();
-  },
-};
-
-export const Camera: Story = {
-  args: {
-    ...empty,
-    kind: "video",
-    enabled: true,
-    busy: false,
-    toggle: fn(),
-    options: [{ id: "cam1", label: { type: "name", name: "Camera 1" } }],
-    selected: "cam1",
-    select: fn(),
-    backgroundEffect: "none",
-    backgroundEffects: [
-      { id: "none", kind: "none" },
-      { id: "blur", kind: "blur" },
-    ],
-    selectBackgroundEffect: fn(),
-  },
-  play: async ({ args, canvasElement }) => {
-    await userEvent.click(
-      within(canvasElement).getByRole("switch", { name: "Stop video" }),
-    );
-    await expect(args.toggle).toHaveBeenCalled();
-  },
-};
-
-export const CameraBusy: Story = {
-  args: { ...Camera.args, busy: true },
-};
-
-/** Opens the effects, for the stories that check what they say. */
-async function openEffects(canvasElement: HTMLElement): Promise<HTMLElement> {
-  await userEvent.click(
-    within(canvasElement).getByRole("button", { name: "Camera" }),
-  );
-  return within(document.body).findByRole("group", {
-    name: "Background effects",
-  });
-}
-
-/** The view model says why; the view says it in words. */
-export const CameraEffectsUnavailable: Story = {
-  args: {
-    ...Camera.args,
-    selectBackgroundEffect: undefined,
-    backgroundEffectNotice: "unavailable",
-  },
-  play: async ({ canvasElement }) => {
-    const section = await openEffects(canvasElement);
-    await expect(
-      within(section).getByRole("group"),
-    ).toHaveAccessibleDescription(
-      "Background effects are not supported on this platform.",
-    );
-  },
-};
-
-export const CameraEffectsSlow: Story = {
-  args: {
-    ...Camera.args,
-    backgroundEffectNotice: "slow",
-  },
-  play: async ({ canvasElement }) => {
-    const section = await openEffects(canvasElement);
-    await expect(
-      within(section).getByRole("group"),
-    ).toHaveAccessibleDescription(
-      "Background effects run slowly on this platform, which may cause your video to stutter.",
-    );
-  },
-};
-
-export const CameraFileRefused: Story = {
-  args: {
-    ...Camera.args,
-    addBackgroundImage: fn(),
-    backgroundImageRefusal: { reason: "not-an-image" },
-  },
-  play: async ({ canvasElement }) => {
-    await openEffects(canvasElement);
-    await expect(
-      await within(document.body).findByText(
-        "That file is not a supported image",
-      ),
-    ).toBeInTheDocument();
-  },
-};
-
-/** No devices to pick and none to mute: a plain, disabled mute button. */
-export const WithoutDevices: Story = {
-  args: {
-    ...Camera.args,
-    enabled: false,
-    toggle: undefined,
-    options: [],
-  },
-  play: async ({ canvasElement }) => {
-    const canvas = within(canvasElement);
-    await expect(
-      canvas.queryByRole("button", { name: "Camera" }),
-    ).not.toBeInTheDocument();
-    await expect(canvas.getByTestId("incall_videomute")).toHaveAttribute(
-      "aria-disabled",
-      "true",
-    );
-  },
-};

src/components/MediaMenuButton.tsx

@@ -1,124 +0,0 @@
-/*
-Copyright 2026 Element Creations Ltd.
-
-SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
-Please see LICENSE in the repository root for full details.
-*/
-
-import { type FC, useMemo } from "react";
-import { useTranslation } from "react-i18next";
-
-import { MicButton, VideoButton } from "../button";
-import { MediaMuteAndSwitchButton } from "./MediaMuteAndSwitchButton";
-import { type MediaMenuViewModel } from "./MediaMenuViewModel";
-import { SelfPreview } from "./SelfPreview";
-import { useBehavior } from "../useBehavior";
-
-interface Props {
-  vm: MediaMenuViewModel;
-  kind: "audio" | "video";
-  size: "md" | "lg";
-}
-
-/**
- * The microphone's or the camera's mute button: with a menu to pick the
- * device while there are devices to offer, a plain mute button otherwise.
- */
-export const MediaMenuButton: FC<Props> = ({ vm, kind, size }) => {
-  const { t } = useTranslation();
-  const enabled = useBehavior(vm.enabled$);
-  const busy = useBehavior(vm.busy$);
-  const toggle = useBehavior(vm.toggle$);
-  const options = useBehavior(vm.options$);
-  const selected = useBehavior(vm.selected$);
-  const select = useBehavior(vm.select$);
-  const outputOptions = useBehavior(vm.outputOptions$);
-  const selectedOutput = useBehavior(vm.selectedOutput$);
-  const selectOutput = useBehavior(vm.selectOutput$);
-  const backgroundEffect = useBehavior(vm.backgroundEffect$);
-  const backgroundEffects = useBehavior(vm.backgroundEffects$);
-  const notice = useBehavior(vm.backgroundEffectNotice$);
-  const settling = useBehavior(vm.backgroundEffectSettling$);
-  const refusal = useBehavior(vm.backgroundImageRefusal$);
-  const selectBackgroundEffect = useBehavior(vm.selectBackgroundEffect$);
-  const addBackgroundImage = useBehavior(vm.addBackgroundImage$);
-  const removeBackgroundEffect = useBehavior(vm.removeBackgroundEffect$);
-  const cameraTrack = useBehavior(vm.cameraTrack$);
-
-  const testId = kind === "audio" ? "incall_mute" : "incall_videomute";
-
-  const noticeText = useMemo(() => {
-    switch (notice) {
-      case undefined:
-        return undefined;
-      case "unavailable":
-        return t("background_effects.unavailable");
-      case "slow":
-        return t("background_effects.slow");
-    }
-  }, [notice, t]);
-  // A new object for each refusal, so the same one twice is shown twice.
-  const refusalMessage = useMemo(() => {
-    switch (refusal?.reason) {
-      case undefined:
-        return undefined;
-      case "not-an-image":
-        return { text: t("error.background_not_an_image") };
-      case "animated":
-        return { text: t("error.background_animated") };
-      case "undecodable":
-        return { text: t("error.background_undecodable") };
-      case "not-kept":
-        return { text: t("error.background_not_kept") };
-    }
-  }, [refusal, t]);
-
-  if (options.length === 0) {
-    const PlainButton = kind === "audio" ? MicButton : VideoButton;
-    return (
-      <PlainButton
-        size={size}
-        enabled={enabled}
-        busy={busy}
-        onClick={toggle}
-        disabled={busy || toggle === undefined}
-        data-testid={testId}
-      />
-    );
-  }
-
-  return kind === "audio" ? (
-    <MediaMuteAndSwitchButton
-      iconsAndLabels="audio"
-      enabled={enabled}
-      busy={busy}
-      onMuteClick={toggle}
-      data-testid={testId}
-      options={options}
-      selectedOption={selected}
-      onSelect={select}
-      outputOptions={outputOptions}
-      selectedOutputOption={selectedOutput}
-      onSelectOutput={selectOutput}
-    />
-  ) : (
-    <MediaMuteAndSwitchButton
-      iconsAndLabels="video"
-      enabled={enabled}
-      busy={busy}
-      onMuteClick={toggle}
-      options={options}
-      selectedOption={selected}
-      onSelect={select}
-      backgroundEffects={backgroundEffects}
-      selectedBackgroundEffect={backgroundEffect}
-      onSelectBackgroundEffect={selectBackgroundEffect}
-      backgroundEffectSettling={settling}
-      onAddBackgroundImage={addBackgroundImage}
-      onRemoveBackgroundEffect={removeBackgroundEffect}
-      selfPreview={<SelfPreview track={cameraTrack} />}
-      backgroundImageRefusal={refusalMessage}
-      backgroundEffectNotice={noticeText}
-    />
-  );
-};

src/components/MediaMenuViewModel.test.ts

@@ -1,284 +0,0 @@
-/*
-Copyright 2026 Element Creations Ltd.
-
-SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
-Please see LICENSE in the repository root for full details.
-*/
-
-import { afterEach, describe, expect, it, vi } from "vitest";
-import { BehaviorSubject, type Observable } from "rxjs";
-import { type LocalVideoMediaTrack } from "@element-hq/matrixrtc-sdk";
-
-import {
-  flushPromises,
-  testScope,
-  mockMuteStates,
-  mockMediaDevices,
-  mockVideoTrack,
-} from "../utils/test";
-import { constant } from "../state/Behavior";
-import { type BackgroundEffectsState } from "../state/BackgroundEffects";
-import type { DeviceLabel } from "../state/MediaDevices";
-import {
-  createAudioMenuViewModel,
-  createCameraMenuViewModel,
-  type MediaMenuViewModel,
-} from "./MediaMenuViewModel";
-import { backgroundEffect as backgroundEffectSetting } from "../settings/settings";
-import { shippedBackgrounds } from "../tracks/backgroundEffectCatalog";
-import type * as BackgroundImages from "../tracks/backgroundImages";
-import {
-  type AddedBackground,
-  addedBackgrounds,
-  maxAddedBackgrounds,
-  UnusableImage,
-} from "../tracks/backgroundImages";
-
-const modernRouteMock = vi.hoisted(() => vi.fn(() => true));
-vi.mock("@livekit/track-processors", () => ({
-  supportsModernBackgroundProcessors: (): boolean => modernRouteMock(),
-}));
-
-const outputSelectionMock = vi.hoisted(() => vi.fn(() => true));
-vi.mock("livekit-client", () => ({
-  supportsAudioOutputSelection: (): boolean => outputSelectionMock(),
-}));
-
-const store = vi.hoisted(() => ({
-  add: vi.fn<(file: Blob) => Promise<string>>(),
-  remove: vi.fn<(id: string) => Promise<void>>(),
-}));
-vi.mock("../tracks/backgroundImages", async (original) => {
-  const { BehaviorSubject } = await import("rxjs");
-  return {
-    ...(await original<typeof BackgroundImages>()),
-    addedBackgrounds: {
-      added$: new BehaviorSubject<AddedBackground[] | undefined>([]),
-      add: store.add,
-      remove: store.remove,
-    },
-  };
-});
-
-const added$ = addedBackgrounds.added$ as BehaviorSubject<
-  AddedBackground[] | undefined
->;
-
-const devices = mockMediaDevices({
-  audioInput: {
-    available$: constant(
-      new Map<string, DeviceLabel>([
-        ["mic1", { type: "number", number: 1 }],
-        ["mic2", { type: "name", name: "Microphone 2" }],
-      ]),
-    ),
-    selected$: constant(undefined),
-    select: vi.fn(),
-  },
-  // As Safari: no outputs listed.
-  audioOutput: {
-    available$: constant(new Map<string, DeviceLabel>()),
-    selected$: constant(undefined),
-    select: vi.fn(),
-  },
-});
-
-function audioMenu(disableSwitcher = false): MediaMenuViewModel {
-  return createAudioMenuViewModel(
-    testScope(),
-    mockMuteStates(),
-    devices,
-    constant(disableSwitcher),
-  );
-}
-
-function cameraMenu({
-  supported = true,
-  disableSwitcher = false,
-  pipeline$ = constant({ supported, processor: undefined }),
-  camera$ = constant(null),
-}: {
-  supported?: boolean;
-  disableSwitcher?: boolean;
-  pipeline$?: Observable<BackgroundEffectsState>;
-  camera$?: Observable<LocalVideoMediaTrack | null>;
-} = {}): MediaMenuViewModel {
-  return createCameraMenuViewModel(
-    testScope(),
-    mockMuteStates(),
-    devices,
-    constant(disableSwitcher),
-    pipeline$,
-    camera$,
-  );
-}
-
-describe("createAudioMenuViewModel", () => {
-  it("lists the devices, unless the switcher is withheld", () => {
-    expect(audioMenu().options$.value).toEqual([
-      { id: "mic1", label: { type: "number", number: 1 } },
-      { id: "mic2", label: { type: "name", name: "Microphone 2" } },
-    ]);
-    expect(audioMenu(true).options$.value).toEqual([]);
-  });
-
-  it("lists no outputs as an empty list, which keeps the section", () => {
-    expect(audioMenu().outputOptions$.value).toEqual([]);
-  });
-
-  it.each([true, false])(
-    "offers to pick an output only where the platform can route to it (%s)",
-    (canRoute) => {
-      outputSelectionMock.mockReturnValue(canRoute);
-      expect(audioMenu().selectOutput$.value !== undefined).toBe(canRoute);
-    },
-  );
-});
-
-describe("createCameraMenuViewModel", () => {
-  afterEach(() => {
-    backgroundEffectSetting.setValue("none");
-    added$.next([]);
-  });
-
-  it("offers effects where they run, saying where they run slowly", () => {
-    modernRouteMock.mockReturnValue(true);
-    const vm = cameraMenu();
-    expect(vm.selectBackgroundEffect$.value).toBeDefined();
-    expect(vm.addBackgroundImage$.value).toBeDefined();
-    expect(vm.backgroundEffectNotice$.value).toBeUndefined();
-
-    modernRouteMock.mockReturnValue(false);
-    const slow = cameraMenu();
-    expect(slow.selectBackgroundEffect$.value).toBeDefined();
-    expect(slow.backgroundEffectNotice$.value).toBe("slow");
-    modernRouteMock.mockReturnValue(true);
-  });
-
-  it("offers nothing while the switcher is withheld", () => {
-    const vm = cameraMenu({ disableSwitcher: true });
-    expect(vm.options$.value).toEqual([]);
-    expect(vm.selectBackgroundEffect$.value).toBeUndefined();
-    expect(vm.backgroundEffectNotice$.value).toBe("unavailable");
-  });
-
-  it("offers nothing once the pipeline fails to build, keeping the choice", () => {
-    backgroundEffectSetting.setValue("blur");
-    const pipeline$ = new BehaviorSubject<BackgroundEffectsState>({
-      supported: true,
-      processor: undefined,
-    });
-    const vm = cameraMenu({ pipeline$ });
-    expect(vm.backgroundEffect$.value).toBe("blur");
-
-    pipeline$.next({ supported: false, processor: undefined });
-    expect(vm.selectBackgroundEffect$.value).toBeUndefined();
-    expect(vm.addBackgroundImage$.value).toBeUndefined();
-    expect(vm.removeBackgroundEffect$.value).toBeUndefined();
-    expect(vm.backgroundEffectNotice$.value).toBe("unavailable");
-    expect(vm.backgroundEffect$.value).toBe("none");
-    expect(backgroundEffectSetting.getValue()).toBe("blur");
-  });
-
-  it("saves the effect chosen, and none for one not on offer", () => {
-    const vm = cameraMenu();
-    vm.selectBackgroundEffect$.value!("image:arc");
-    expect(vm.backgroundEffect$.value).toBe("image:arc");
-    vm.selectBackgroundEffect$.value!("image:gone");
-    expect(backgroundEffectSetting.getValue()).toBe("none");
-  });
-
-  it("offers every effect in order, the added ones removable", () => {
-    added$.next([{ id: "mine", url: "blob:mine" }]);
-    expect(cameraMenu().backgroundEffects$.value).toEqual([
-      { id: "none", kind: "none", removable: false },
-      { id: "blur", kind: "blur", removable: false },
-      ...shippedBackgrounds.map((background) => ({
-        id: `image:${background.id}`,
-        kind: "image",
-        imageUrl: background.imagePath,
-        removable: false,
-      })),
-      {
-        id: "added:mine",
-        kind: "image",
-        imageUrl: "blob:mine",
-        removable: true,
-      },
-    ]);
-  });
-
-  it("passes on the wait for the first effect", () => {
-    const pipeline$ = new BehaviorSubject<BackgroundEffectsState>({
-      supported: true,
-      processor: undefined,
-      wait: "settling",
-    });
-    const vm = cameraMenu({ pipeline$ });
-    expect(vm.backgroundEffectSettling$.value).toBe(true);
-    pipeline$.next({ ...pipeline$.value, wait: undefined });
-    expect(vm.backgroundEffectSettling$.value).toBe(false);
-  });
-
-  it("offers adding only below the limit", () => {
-    const vm = cameraMenu();
-    added$.next(
-      Array.from({ length: maxAddedBackgrounds }, (_, i) => ({
-        id: `${i}`,
-        url: `blob:${i}`,
-      })),
-    );
-    expect(vm.addBackgroundImage$.value).toBeUndefined();
-    added$.next(added$.value!.slice(1));
-    expect(vm.addBackgroundImage$.value).toBeDefined();
-  });
-
-  it("says why each refused file was refused", async () => {
-    const vm = cameraMenu();
-    store.add.mockRejectedValue(new UnusableImage("animated"));
-    vm.addBackgroundImage$.value!(new File(["x"], "a.gif"));
-    await flushPromises();
-    const first = vm.backgroundImageRefusal$.value;
-    expect(first).toEqual({ reason: "animated" });
-
-    // The same again is a refusal of its own, so it is shown again.
-    vm.addBackgroundImage$.value!(new File(["x"], "a.gif"));
-    await flushPromises();
-    expect(vm.backgroundImageRefusal$.value).toEqual({ reason: "animated" });
-    expect(vm.backgroundImageRefusal$.value).not.toBe(first);
-
-    store.add.mockRejectedValue(new Error("quota"));
-    vm.addBackgroundImage$.value!(new File(["x"], "b.png"));
-    await flushPromises();
-    expect(vm.backgroundImageRefusal$.value).toEqual({ reason: "not-kept" });
-
-    store.add.mockResolvedValue("kept");
-    vm.addBackgroundImage$.value!(new File(["x"], "c.png"));
-    await flushPromises();
-    expect(vm.backgroundImageRefusal$.value).toBeUndefined();
-  });
-
-  it("never removes the selected background", () => {
-    store.remove.mockResolvedValue();
-    const vm = cameraMenu();
-    backgroundEffectSetting.setValue("added:worn");
-    vm.removeBackgroundEffect$.value!("added:worn");
-    expect(store.remove).not.toHaveBeenCalled();
-    vm.removeBackgroundEffect$.value!("added:spare");
-    expect(store.remove).toHaveBeenCalledWith("spare");
-  });
-
-  it("previews the camera only while there is one and it is not muted", () => {
-    const muted$ = new BehaviorSubject(false);
-    const track = mockVideoTrack({ muted$ });
-    const camera$ = new BehaviorSubject<LocalVideoMediaTrack | null>(track);
-    const vm = cameraMenu({ camera$ });
-    expect(vm.cameraTrack$.value).toBe(track);
-    muted$.next(true);
-    expect(vm.cameraTrack$.value).toBeNull();
-    muted$.next(false);
-    expect(vm.cameraTrack$.value).toBe(track);
-    camera$.next(null);
-    expect(vm.cameraTrack$.value).toBeNull();
-  });
-});

src/components/MediaMenuViewModel.ts

@@ -1,316 +0,0 @@
-/*
-Copyright 2026 Element Creations Ltd.
-
-SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
-Please see LICENSE in the repository root for full details.
-*/
-
-import {
-  BehaviorSubject,
-  combineLatest,
-  distinctUntilChanged,
-  map,
-  type Observable,
-  of,
-  switchMap,
-} from "rxjs";
-import { supportsAudioOutputSelection } from "livekit-client";
-import { type LocalVideoMediaTrack } from "@element-hq/matrixrtc-sdk";
-import { supportsModernBackgroundProcessors } from "@livekit/track-processors";
-import { logger } from "matrix-js-sdk/lib/logger";
-
-import {
-  parseEffect,
-  serializeEffect,
-  shippedBackgrounds,
-} from "../tracks/backgroundEffectCatalog";
-import {
-  type AddedBackground,
-  addedBackgrounds,
-  maxAddedBackgrounds,
-  type UnusableReason,
-  UnusableImage,
-} from "../tracks/backgroundImages";
-import { type BackgroundEffectsState } from "../state/BackgroundEffects";
-import { type MenuOptions } from "./MediaMuteAndSwitchButton";
-import { type MediaDevices } from "../state/MediaDevices";
-import { backgroundEffect as backgroundEffectSetting } from "../settings/settings";
-import { type Behavior, constant } from "../state/Behavior";
-import type { ObservableScope } from "../state/ObservableScope";
-import { type MuteStates } from "../state/MuteStates";
-import { createStaticViewModel, type ViewModel } from "../state/ViewModel";
-import { type BackgroundEffectGridItem } from "./BackgroundEffectGrid";
-
-export interface BackgroundImageRefusal {
-  reason: UnusableReason | "not-kept";
-}
-
-/**
- * A mute button with a menu to pick the device, shared by the microphone and
- * the camera. Fields that belong to the other device are left empty.
- */
-export interface MediaMenuSnapshot {
-  enabled: boolean;
-  busy: boolean;
-  /** Also controls if the button is disabled */
-  toggle: (() => void) | undefined;
-  /** No options leave out the menu, which is then a plain mute button. */
-  options: MenuOptions[];
-  selected: string | undefined;
-  select: ((id: string) => void) | undefined;
-
-  /** Output (speaker) devices. Microphone only. */
-  outputOptions: MenuOptions[];
-  selectedOutput: string | undefined;
-  /** Undefined where the platform can't route audio to a chosen device. */
-  selectOutput: ((id: string) => void) | undefined;
-
-  /** The selected background effect, as its option id. Camera only. */
-  backgroundEffect: string | undefined;
-  /** Every effect on offer, in the order they are shown. */
-  backgroundEffects: BackgroundEffectGridItem[];
-  /** What the user is told about effects here, if anything. */
-  backgroundEffectNotice: "unavailable" | "slow" | undefined;
-  /** Whether the first effect chosen is still being prepared. */
-  backgroundEffectSettling: boolean;
-  /** Why the last file offered couldn't be kept, if it couldn't. */
-  backgroundImageRefusal: BackgroundImageRefusal | undefined;
-  /** Undefined where background effects can't be chosen. */
-  selectBackgroundEffect: ((id: string) => void) | undefined;
-  /** Undefined where no background can be added. */
-  addBackgroundImage: ((file: File) => void) | undefined;
-  /** Removes an added background by its option id, unless it is the selected one. */
-  removeBackgroundEffect: ((id: string) => void) | undefined;
-  /** The camera to preview, with the selected effect; null while it is off. */
-  cameraTrack: LocalVideoMediaTrack | null;
-}
-
-export type MediaMenuViewModel = ViewModel<MediaMenuSnapshot>;
-
-const noBackgroundEffects = {
-  backgroundEffect: undefined,
-  backgroundEffects: [],
-  backgroundEffectNotice: undefined,
-  backgroundEffectSettling: false,
-  backgroundImageRefusal: undefined,
-  selectBackgroundEffect: undefined,
-  addBackgroundImage: undefined,
-  removeBackgroundEffect: undefined,
-  cameraTrack: null,
-} satisfies Partial<MediaMenuSnapshot>;
-
-function options$(
-  disableSwitcher$: Behavior<boolean>,
-  available$: Behavior<Map<string, MenuOptions["label"]>>,
-): Observable<MenuOptions[]> {
-  return disableSwitcher$.pipe(
-    switchMap((disable) =>
-      disable
-        ? constant([] as MenuOptions[])
-        : available$.pipe(
-            map((available) =>
-              [...available.entries()].map(([id, label]) => ({ id, label })),
-            ),
-          ),
-    ),
-  );
-}
-
-/**
- * The microphone's mute button and menu, with the speaker choice.
- *
- * @param disableSwitcher$ - True to leave out the menu.
- */
-export function createAudioMenuViewModel(
-  scope: ObservableScope,
-  muteStates: MuteStates,
-  mediaDevices: MediaDevices,
-  disableSwitcher$: Behavior<boolean>,
-): MediaMenuViewModel {
-  const { audio } = muteStates;
-  return {
-    ...createStaticViewModel(noBackgroundEffects),
-    enabled$: audio.enabled$,
-    busy$: audio.syncing$,
-    toggle$: scope.behavior(audio.toggle$.pipe(map((t) => t ?? undefined))),
-    options$: scope.behavior(
-      options$(disableSwitcher$, mediaDevices.audioInput.available$),
-    ),
-    selected$: scope.behavior(
-      mediaDevices.audioInput.selected$.pipe(map((s) => s?.id)),
-    ),
-    select$: constant(mediaDevices.audioInput.select),
-    outputOptions$: scope.behavior(
-      options$(disableSwitcher$, mediaDevices.audioOutput.available$),
-    ),
-    selectedOutput$: scope.behavior(
-      mediaDevices.audioOutput.selected$.pipe(map((s) => s?.id)),
-    ),
-    // Withheld where the platform can't route audio to a chosen device, which
-    // disables the speaker section.
-    selectOutput$: constant(
-      supportsAudioOutputSelection()
-        ? mediaDevices.audioOutput.select
-        : undefined,
-    ),
-  };
-}
-
-/**
- * The camera's mute button and menu, with the background effects and a
- * preview of the camera.
- *
- * @param disableSwitcher$ - True to leave out the menu.
- * @param backgroundEffectsState$ - The background pipeline's state: whether
- *   effects run here, and the wait for the first.
- * @param camera$ - The camera as the pipeline has it, for the preview.
- */
-export function createCameraMenuViewModel(
-  scope: ObservableScope,
-  muteStates: MuteStates,
-  mediaDevices: MediaDevices,
-  disableSwitcher$: Behavior<boolean>,
-  backgroundEffectsState$: Observable<BackgroundEffectsState>,
-  camera$: Observable<LocalVideoMediaTrack | null | undefined>,
-): MediaMenuViewModel {
-  const { video } = muteStates;
-  // Also false once the pipeline has failed to build this session.
-  const supported$ = backgroundEffectsState$.pipe(
-    map(({ supported }) => supported === true),
-    distinctUntilChanged(),
-  );
-  const slow = !supportsModernBackgroundProcessors();
-  const offered$ = combineLatest([disableSwitcher$, supported$]).pipe(
-    map(([switcherDisabled, supported]) => !switcherDisabled && supported),
-  );
-  // A new object for each refusal, so the same one twice is shown twice.
-  const refusal$ = new BehaviorSubject<BackgroundImageRefusal | undefined>(
-    undefined,
-  );
-  return {
-    ...createStaticViewModel({
-      outputOptions: [],
-      selectedOutput: undefined,
-      selectOutput: undefined,
-    }),
-    enabled$: video.enabled$,
-    busy$: video.syncing$,
-    toggle$: scope.behavior(video.toggle$.pipe(map((t) => t ?? undefined))),
-    options$: scope.behavior(
-      options$(disableSwitcher$, mediaDevices.videoInput.available$),
-    ),
-    selected$: scope.behavior(
-      mediaDevices.videoInput.selected$.pipe(map((s) => s?.id)),
-    ),
-    select$: constant(mediaDevices.videoInput.select),
-    backgroundEffect$: scope.behavior(
-      combineLatest([backgroundEffectSetting.value$, supported$]).pipe(
-        map(([raw, supported]) =>
-          supported ? serializeEffect(parseEffect(raw)) : "none",
-        ),
-      ),
-    ),
-    selectBackgroundEffect$: scope.behavior(
-      offered$.pipe(
-        map((offered) =>
-          offered
-            ? (id: string): void =>
-                backgroundEffectSetting.setValue(
-                  serializeEffect(parseEffect(id)),
-                )
-            : undefined,
-        ),
-      ),
-    ),
-    backgroundEffects$: scope.behavior(
-      addedBackgrounds.added$.pipe(
-        map((added) => backgroundEffectChoices(added ?? [])),
-      ),
-    ),
-    backgroundEffectNotice$: scope.behavior(
-      offered$.pipe(
-        map((offered) =>
-          !offered ? "unavailable" : slow ? "slow" : undefined,
-        ),
-      ),
-    ),
-    backgroundEffectSettling$: scope.behavior(
-      backgroundEffectsState$.pipe(
-        map(({ wait }) => wait !== undefined),
-        distinctUntilChanged(),
-      ),
-      false,
-    ),
-    // Kept and offered, not put on: that waits for the user to choose it.
-    addBackgroundImage$: scope.behavior(
-      combineLatest([offered$, addedBackgrounds.added$]).pipe(
-        map(([offered, added]) =>
-          offered && (added?.length ?? 0) < maxAddedBackgrounds
-            ? (file: File): void => {
-                refusal$.next(undefined);
-                addedBackgrounds.add(file).catch((e) => {
-                  logger.warn("Could not keep that background", e);
-                  refusal$.next({
-                    reason: e instanceof UnusableImage ? e.reason : "not-kept",
-                  });
-                });
-              }
-            : undefined,
-        ),
-      ),
-    ),
-    backgroundImageRefusal$: refusal$,
-    // None while muted: the call mutes its track rather than releasing it.
-    cameraTrack$: scope.behavior(
-      camera$.pipe(
-        switchMap((camera) =>
-          camera
-            ? camera.muted$.pipe(map((muted) => (muted ? null : camera)))
-            : of(null),
-        ),
-      ),
-      null,
-    ),
-    removeBackgroundEffect$: scope.behavior(
-      offered$.pipe(
-        map((offered) =>
-          offered
-            ? (optionId: string): void => {
-                const effect = parseEffect(optionId);
-                if (effect.kind !== "added") return;
-                // The selected effect can't be removed: that would leave no
-                // effect selected.
-                if (backgroundEffectSetting.getValue() === optionId) return;
-                addedBackgrounds
-                  .remove(effect.id)
-                  .catch((e) =>
-                    logger.warn("Could not remove that background", e),
-                  );
-              }
-            : undefined,
-        ),
-      ),
-    ),
-  };
-}
-
-function backgroundEffectChoices(
-  added: AddedBackground[],
-): BackgroundEffectGridItem[] {
-  return [
-    { id: serializeEffect({ kind: "none" }), kind: "none", removable: false },
-    { id: serializeEffect({ kind: "blur" }), kind: "blur", removable: false },
-    ...shippedBackgrounds.map((background) => ({
-      id: serializeEffect({ kind: "shipped", id: background.id }),
-      kind: "image" as const,
-      imageUrl: background.imagePath,
-      removable: false,
-    })),
-    ...added.map((background) => ({
-      id: serializeEffect({ kind: "added", id: background.id }),
-      kind: "image" as const,
-      imageUrl: background.url,
-      removable: true,
-    })),
-  ];
-}

src/components/MediaMuteAndSwitchButton.stories.tsx

@@ -440,7 +440,7 @@ function swatch(colour: string): string {
   )}`;
 }
 
-/** One's own backgrounds are removable, unless one is the selected one. */
+/** One's own backgrounds are removable, never the one in force. */
 export const AddedBackgroundsCanBeRemoved: Story = {
   args: {
     ...VideoUnmute.args,

src/components/MediaMuteAndSwitchButton.tsx

@@ -85,7 +85,7 @@ export interface MediaMuteAndSwitchButtonProps {
   backgroundEffectSettling?: boolean;
   /** Called with the file chosen from the add tile. Omit to leave it out. */
   onAddBackgroundImage?: (file: File) => void;
-  /** Removes a removable effect, unless it is the selected one. */
+  /** Removes a removable effect, never the one in force. */
   onRemoveBackgroundEffect?: (id: string) => void;
   /** Why the last file offered couldn't be used; a new object each time. */
   backgroundImageRefusal?: { text: string };

src/components/SelfPreview.test.tsx

@@ -28,10 +28,8 @@ describe("SelfPreview", () => {
     expect(track.detach).toHaveBeenCalledExactlyOnceWith(a);
   });
 
-  it("mirrors the camera unless it faces away", () => {
-    const facingMode$ = new BehaviorSubject<"user" | "environment" | undefined>(
-      "user",
-    );
+  it("mirrors the camera while it faces the user, and only then", () => {
+    const facingMode$ = new BehaviorSubject<"user" | "environment">("user");
     const { container } = render(
       <SelfPreview track={mockVideoTrack({ facingMode$ })} />,
     );
@@ -39,9 +37,6 @@ describe("SelfPreview", () => {
     expect(video().classList.contains(styles.mirrored)).toBe(true);
     act(() => facingMode$.next("environment"));
     expect(video().classList.contains(styles.mirrored)).toBe(false);
-    // As the built-in camera of a Mac, which doesn't say
-    act(() => facingMode$.next(undefined));
-    expect(video().classList.contains(styles.mirrored)).toBe(true);
   });
 
   it("says the camera is off while there is none", () => {

src/components/SelfPreview.tsx

@@ -11,7 +11,6 @@ import { VideoCallOffIcon } from "@vector-im/compound-design-tokens/assets/web/i
 
 import styles from "./SelfPreview.module.css";
 import { useBehavior } from "../useBehavior";
-import { mirrors } from "../utils/media";
 
 const noFacingMode = constant(undefined);
 
@@ -43,7 +42,7 @@ export const SelfPreview: FC<Props> = ({ track }) => {
       ref={videoRef}
       muted
       playsInline
-      className={mirrors(facingMode) ? styles.mirrored : undefined}
+      className={facingMode === "user" ? styles.mirrored : undefined}
     />
   );
 };

src/config/Config.test.ts

@@ -108,6 +108,22 @@ describe("Config.initWith", () => {
     expect(Config.get().media_quality).toEqual(DEFAULT_CONFIG.media_quality);
   });
 
+  it("falls back to the defaults when config.json is not JSON", async () => {
+    vi.spyOn(globalThis, "fetch").mockResolvedValue(
+      new Response("<!doctype html><title>Element</title>", {
+        status: 200,
+        headers: { "content-type": "text/html" },
+      }),
+    );
+    const warnSpy = vi.spyOn(logger, "warn").mockImplementation(() => {});
+    Reflect.set(Config, "internalInstance", undefined);
+
+    await expect(Config.init()).resolves.toBeUndefined();
+
+    expect(Config.get().media_quality).toEqual(DEFAULT_CONFIG.media_quality);
+    expect(warnSpy).toHaveBeenCalledTimes(1);
+  });
+
   it("replaces a config initialized earlier", () => {
     Config.initWith({ ssla: "https://first.invalid/ssla" });
     Config.initWith({ ssla: "https://second.invalid/ssla" });

src/config/Config.ts

@@ -156,5 +156,10 @@ async function downloadConfig(fetchTarget: string): Promise<ConfigOptions> {
     return {};
   }
 
-  return response.json();
+  try {
+    return await response.json();
+  } catch (e) {
+    logger.warn(`Config at ${fetchTarget} is not JSON, using defaults`, e);
+    return {};
+  }
 }

src/home/HomePage.test.tsx

@@ -0,0 +1,62 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { expect, test, vi } from "vitest";
+import { render, screen } from "@testing-library/react";
+import { BrowserRouter } from "react-router-dom";
+import { type MatrixClient } from "matrix-js-sdk";
+import { BehaviorSubject } from "rxjs";
+
+import { HomePage } from "./HomePage";
+import { ClientContextProvider } from "../ClientContext";
+import { type ClientSessionState } from "../state/ClientSession";
+
+vi.mock("./RegisteredView", () => ({
+  RegisteredView: ({ client }: { client: MatrixClient }) => (
+    <span>registered as {client.getUserId()}</span>
+  ),
+}));
+vi.mock("./UnauthenticatedView", () => ({
+  UnauthenticatedView: () => <span>unauthenticated</span>,
+}));
+
+test("waits for the session to be restored", () => {
+  renderHome({ state: "loading" });
+  expect(screen.getByRole("heading", { name: "Loading…" })).toBeVisible();
+});
+
+test("shows the session's error", () => {
+  vi.spyOn(console, "error").mockImplementation(() => {});
+  renderHome({ state: "error", error: new Error("Opened elsewhere") });
+  expect(screen.getByText("Something went wrong")).toBeVisible();
+});
+
+test("welcomes a signed-in user", () => {
+  renderHome({
+    state: "signedIn",
+    client: { getUserId: () => "@alice:example.org" } as MatrixClient,
+    passwordlessUser: false,
+  });
+  expect(screen.getByText("registered as @alice:example.org")).toBeVisible();
+});
+
+test("invites a signed-out user to start a call", () => {
+  renderHome({ state: "signedOut" });
+  expect(screen.getByText("unauthenticated")).toBeVisible();
+});
+
+function renderHome(state: ClientSessionState): void {
+  render(
+    <BrowserRouter>
+      <ClientContextProvider
+        value={{ state$: new BehaviorSubject<ClientSessionState>(state) }}
+      >
+        <HomePage />
+      </ClientContextProvider>
+    </BrowserRouter>,
+  );
+}

src/home/HomePage.tsx

@@ -8,7 +8,7 @@ Please see LICENSE in the repository root for full details.
 import { useTranslation } from "react-i18next";
 import { type FC } from "react";
 
-import { useClientState } from "../ClientContext";
+import { useClientSessionState } from "../ClientContext";
 import { ErrorPage, LoadingPage } from "../FullScreenView";
 import { UnauthenticatedView } from "./UnauthenticatedView";
 import { RegisteredView } from "./RegisteredView";
@@ -18,17 +18,16 @@ export const HomePage: FC = () => {
   const { t } = useTranslation();
   usePageTitle(t("common.home"));
 
-  const clientState = useClientState();
+  const session = useClientSessionState();
 
-  if (!clientState) {
-    return <LoadingPage />;
-  } else if (clientState.state === "error") {
-    return <ErrorPage error={clientState.error} />;
-  } else {
-    return clientState.authenticated ? (
-      <RegisteredView client={clientState.authenticated.client} />
-    ) : (
-      <UnauthenticatedView />
-    );
+  switch (session.state) {
+    case "loading":
+      return <LoadingPage />;
+    case "error":
+      return <ErrorPage error={session.error} />;
+    case "signedIn":
+      return <RegisteredView client={session.client} />;
+    case "signedOut":
+      return <UnauthenticatedView />;
   }
 };

src/home/UnauthenticatedView.test.tsx

@@ -0,0 +1,136 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { afterEach, expect, test, vi } from "vitest";
+import { render, screen } from "@testing-library/react";
+import userEvent from "@testing-library/user-event";
+import { type FC } from "react";
+import { MemoryRouter, useLocation } from "react-router-dom";
+import { type MatrixClient } from "matrix-js-sdk";
+
+import { UnauthenticatedView } from "./UnauthenticatedView";
+import { ClientManagerProvider } from "../ClientContext";
+import { type ClientManager } from "../state/ClientSession";
+import { computeUrlParams, UrlParamsProvider } from "../UrlParams";
+import type * as matrixUtils from "../utils/matrix";
+import { createRoom, getRelativeRoomUrl } from "../utils/matrix";
+import { E2eeType } from "../e2ee/e2eeType";
+
+vi.mock("../auth/useRecaptcha", () => ({
+  useRecaptcha: () => ({
+    execute: vi.fn().mockResolvedValue("captcha-response"),
+    reset,
+    recaptchaId: "recaptcha",
+  }),
+}));
+vi.mock("../auth/useRegistrationTerms", () => ({
+  useRegistrationTerms: () => ({ recaptchaKey: "site-key" }),
+}));
+vi.mock("../auth/generateRandomName", () => ({
+  generateRandomName: () => "Random Name",
+}));
+vi.mock("../utils/matrix", async (importOriginal) => ({
+  ...(await importOriginal<typeof matrixUtils>()),
+  createRoom: vi.fn(),
+}));
+vi.mock("../UserMenuContainer", () => ({ UserMenuContainer: () => null }));
+
+const reset = vi.fn();
+const client = {} as MatrixClient;
+
+afterEach(() => vi.clearAllMocks());
+
+test("registers a guest, creates their call and signs them in", async () => {
+  const manager = mockManager();
+  const setSignedIn = vi.fn();
+  vi.mocked(manager.register).mockResolvedValue({ client, setSignedIn });
+  vi.mocked(createRoom).mockResolvedValue({
+    roomId: "!call:example.org",
+    alias: "#my-call:example.org",
+    password: "secret",
+  });
+  renderView(manager);
+
+  await submit("My Call", "Alice");
+
+  expect(manager.register).toHaveBeenCalledWith(
+    "Random Name",
+    expect.stringMatching(/^.{16}$/),
+    "Alice",
+    "captcha-response",
+    true,
+  );
+  expect(createRoom).toHaveBeenCalledWith(
+    client,
+    "My Call",
+    E2eeType.SHARED_KEY,
+  );
+  expect(setSignedIn).toHaveBeenCalled();
+  const url = getRelativeRoomUrl(
+    "!call:example.org",
+    { kind: E2eeType.SHARED_KEY, secret: "secret" },
+    "My Call",
+  );
+  expect(await screen.findByText(`at ${url}`)).toBeVisible();
+});
+
+test("signs in only once the user chooses to join a call that exists", async () => {
+  const manager = mockManager();
+  const setSignedIn = vi.fn();
+  vi.mocked(manager.register).mockResolvedValue({ client, setSignedIn });
+  vi.mocked(createRoom).mockRejectedValue({ errcode: "M_ROOM_IN_USE" });
+  renderView(manager);
+
+  await submit("My Call", "Alice");
+
+  const join = await screen.findByRole("button", { name: "Yes, join call" });
+  expect(setSignedIn).not.toHaveBeenCalled();
+  await userEvent.click(join);
+  expect(setSignedIn).toHaveBeenCalled();
+  expect(await screen.findByText("at /my-call")).toBeVisible();
+});
+
+test("shows why registering failed and resets the captcha", async () => {
+  const manager = mockManager();
+  vi.mocked(manager.register).mockRejectedValue(new Error("Rate limited"));
+  renderView(manager);
+
+  await submit("My Call", "Alice");
+
+  expect(await screen.findByText("Rate limited")).toBeVisible();
+  expect(reset).toHaveBeenCalled();
+  expect(createRoom).not.toHaveBeenCalled();
+});
+
+async function submit(callName: string, displayName: string): Promise<void> {
+  const user = userEvent.setup();
+  await user.type(screen.getByTestId("home_callName"), callName);
+  await user.type(screen.getByTestId("home_displayName"), displayName);
+  await user.click(screen.getByTestId("home_go"));
+}
+
+function mockManager(): ClientManager {
+  return { login: vi.fn(), register: vi.fn(), logout: vi.fn() };
+}
+
+const WhereAmI: FC = () => {
+  const { pathname, search, hash } = useLocation();
+  return <span>{`at ${pathname}${search}${hash}`}</span>;
+};
+
+function renderView(manager: ClientManager): void {
+  render(
+    <MemoryRouter initialEntries={["/"]}>
+      <UrlParamsProvider value={computeUrlParams()}>
+        <ClientManagerProvider value={manager}>
+          <UnauthenticatedView />
+          <WhereAmI />
+        </ClientManagerProvider>
+      </UrlParamsProvider>
+    </MemoryRouter>,
+  );
+}

src/home/UnauthenticatedView.tsx

@@ -12,7 +12,7 @@ import { Button, Heading, Text } from "@vector-im/compound-web";
 import { logger } from "matrix-js-sdk/lib/logger";
 import { useNavigate } from "react-router-dom";
 
-import { useClient } from "../ClientContext";
+import { useClientManager } from "../ClientContext";
 import { Header, HeaderLogo, LeftNav, RightNav } from "../Header";
 import { UserMenuContainer } from "../UserMenuContainer";
 import { FieldRow, InputField, ErrorMessage } from "../input/Input";
@@ -22,7 +22,7 @@ import {
   roomAliasLocalpartFromRoomName,
   sanitiseRoomNameInput,
 } from "../utils/matrix";
-import { useInteractiveRegistration } from "../auth/useInteractiveRegistration";
+import { useRegistrationTerms } from "../auth/useRegistrationTerms";
 import { JoinExistingCallModal } from "./JoinExistingCallModal";
 import { useRecaptcha } from "../auth/useRecaptcha";
 import { Form } from "../form/Form";
@@ -37,12 +37,12 @@ import { ExternalLink, Link } from "../button/Link";
 import { useUrlParams } from "../UrlParams";
 
 export const UnauthenticatedView: FC = () => {
-  const { setClient } = useClient();
+  const { register } = useClientManager();
   const { header } = useUrlParams();
   const [loading, setLoading] = useState(false);
   const [error, setError] = useState<Error>();
   const [optInAnalytics] = useOptInAnalytics();
-  const { recaptchaKey, register } = useInteractiveRegistration();
+  const { recaptchaKey } = useRegistrationTerms();
   const { execute, reset, recaptchaId } = useRecaptcha(recaptchaKey);
 
   const [joinExistingCallModalOpen, setJoinExistingCallModalOpen] =
@@ -67,7 +67,9 @@ export const UnauthenticatedView: FC = () => {
         setLoading(true);
         const recaptchaResponse = await execute();
         const userName = generateRandomName();
-        const [client, session] = await register(
+        // Signed in only once the call exists too: this view is replaced the
+        // moment the session has a user, and the call is what they came for
+        const { client, setSignedIn } = await register(
           userName,
           secureRandomString(16),
           displayName,
@@ -83,15 +85,12 @@ export const UnauthenticatedView: FC = () => {
             E2eeType.SHARED_KEY,
           );
         } catch (error) {
-          if (!setClient) {
-            throw error;
-          }
-
           // eslint-disable-next-line @typescript-eslint/ban-ts-comment
           // @ts-ignore
           if (error.errcode === "M_ROOM_IN_USE") {
-            setOnFinished(() => {
-              setClient(client, session);
+            // Wrapped once more, as a bare function would be taken for an updater
+            setOnFinished(() => () => {
+              setSignedIn();
               const aliasLocalpart = roomAliasLocalpartFromRoomName(roomName);
               navigate(`/${aliasLocalpart}`)?.catch((error) => {
                 logger.error("Failed to navigate to alias localpart", error);
@@ -106,14 +105,10 @@ export const UnauthenticatedView: FC = () => {
           }
         }
 
-        // Only consider the registration successful if we managed to create the room, too
-        if (!setClient) {
-          throw new Error("setClient is undefined");
-        }
         if (!createRoomResult.password)
           throw new Error("Failed to create room with shared secret");
 
-        setClient(client, session);
+        setSignedIn();
         await navigate(
           getRelativeRoomUrl(
             createRoomResult.roomId,
@@ -130,14 +125,7 @@ export const UnauthenticatedView: FC = () => {
         reset();
       });
     },
-    [
-      register,
-      reset,
-      execute,
-      navigate,
-      setJoinExistingCallModalOpen,
-      setClient,
-    ],
+    [register, reset, execute, navigate, setJoinExistingCallModalOpen],
   );
 
   return (

src/main.tsx

@@ -20,7 +20,9 @@ import { App } from "./App";
 import { init as initRageshake } from "./settings/rageshake";
 import { Initializer } from "./initializer";
 import { AppViewModel } from "./state/AppViewModel";
+import { pendingHostClientSession } from "./state/ClientSession";
 import { globalScope } from "./state/ObservableScope";
+import { StandaloneClientSession } from "./state/StandaloneClientSession";
 import { getUrlParams } from "./UrlParams";
 
 initRageshake().catch((e) => {
@@ -51,17 +53,25 @@ if (fatalError !== null) {
 Initializer.initBeforeReact()
   .then((widget) => {
     const { controlledAudioDevices, callIntent } = getUrlParams();
+    // As a widget, the client comes from the host over the widget API, and
+    // the session is the host's. Standalone, Element Call restores or creates
+    // a session of its own, which it also manages.
+    const options = { controlledAudioDevices, callIntent };
+    let vm: AppViewModel;
+    if (widget === null) {
+      const session = new StandaloneClientSession(globalScope);
+      vm = new AppViewModel(globalScope, options, session, session);
+    } else {
+      vm = new AppViewModel(
+        globalScope,
+        options,
+        pendingHostClientSession(globalScope, widget.client),
+        null,
+      );
+    }
     root.render(
       <StrictMode>
-        <App
-          vm={
-            new AppViewModel(globalScope, {
-              controlledAudioDevices,
-              callIntent,
-            })
-          }
-          widget={widget}
-        />
+        <App vm={vm} widget={widget} />
       </StrictMode>,
     );
   })

src/reactions/index.ts

@@ -7,30 +7,30 @@ Please see LICENSE in the repository root for full details.
 
 import { type RelationType } from "matrix-js-sdk";
 
-import catSoundOgg from "../sound/reactions/cat.ogg?url";
-import catSoundMp3 from "../sound/reactions/cat.mp3?url";
-import clapSoundOgg from "../sound/reactions/clap.ogg?url";
-import clapSoundMp3 from "../sound/reactions/clap.mp3?url";
-import cricketsSoundOgg from "../sound/reactions/crickets.ogg?url";
-import cricketsSoundMp3 from "../sound/reactions/crickets.mp3?url";
-import dogSoundOgg from "../sound/reactions/dog.ogg?url";
-import dogSoundMp3 from "../sound/reactions/dog.mp3?url";
-import genericSoundOgg from "../sound/reactions/generic.ogg?url";
-import genericSoundMp3 from "../sound/reactions/generic.mp3?url";
-import lightbulbSoundOgg from "../sound/reactions/lightbulb.ogg?url";
-import lightbulbSoundMp3 from "../sound/reactions/lightbulb.mp3?url";
-import partySoundOgg from "../sound/reactions/party.ogg?url";
-import partySoundMp3 from "../sound/reactions/party.mp3?url";
-import deerSoundOgg from "../sound/reactions/deer.ogg?url";
-import deerSoundMp3 from "../sound/reactions/deer.mp3?url";
-import rockSoundOgg from "../sound/reactions/rock.ogg?url";
-import rockSoundMp3 from "../sound/reactions/rock.mp3?url";
-import waveSoundOgg from "../sound/reactions/wave.ogg?url";
-import waveSoundMp3 from "../sound/reactions/wave.mp3?url";
-import baduntssSoundOgg from "../sound/reactions/baduntss.ogg?url";
-import baduntssSoundMp3 from "../sound/reactions/baduntss.mp3?url";
-import bellSoundOgg from "../sound/reactions/bell.ogg?url";
-import bellSoundMp3 from "../sound/reactions/bell.mp3?url";
+import catSoundOgg from "../sound/reactions/cat.ogg?url&no-inline";
+import catSoundMp3 from "../sound/reactions/cat.mp3?url&no-inline";
+import clapSoundOgg from "../sound/reactions/clap.ogg?url&no-inline";
+import clapSoundMp3 from "../sound/reactions/clap.mp3?url&no-inline";
+import cricketsSoundOgg from "../sound/reactions/crickets.ogg?url&no-inline";
+import cricketsSoundMp3 from "../sound/reactions/crickets.mp3?url&no-inline";
+import dogSoundOgg from "../sound/reactions/dog.ogg?url&no-inline";
+import dogSoundMp3 from "../sound/reactions/dog.mp3?url&no-inline";
+import genericSoundOgg from "../sound/reactions/generic.ogg?url&no-inline";
+import genericSoundMp3 from "../sound/reactions/generic.mp3?url&no-inline";
+import lightbulbSoundOgg from "../sound/reactions/lightbulb.ogg?url&no-inline";
+import lightbulbSoundMp3 from "../sound/reactions/lightbulb.mp3?url&no-inline";
+import partySoundOgg from "../sound/reactions/party.ogg?url&no-inline";
+import partySoundMp3 from "../sound/reactions/party.mp3?url&no-inline";
+import deerSoundOgg from "../sound/reactions/deer.ogg?url&no-inline";
+import deerSoundMp3 from "../sound/reactions/deer.mp3?url&no-inline";
+import rockSoundOgg from "../sound/reactions/rock.ogg?url&no-inline";
+import rockSoundMp3 from "../sound/reactions/rock.mp3?url&no-inline";
+import waveSoundOgg from "../sound/reactions/wave.ogg?url&no-inline";
+import waveSoundMp3 from "../sound/reactions/wave.mp3?url&no-inline";
+import baduntssSoundOgg from "../sound/reactions/baduntss.ogg?url&no-inline";
+import baduntssSoundMp3 from "../sound/reactions/baduntss.mp3?url&no-inline";
+import bellSoundOgg from "../sound/reactions/bell.ogg?url&no-inline";
+import bellSoundMp3 from "../sound/reactions/bell.mp3?url&no-inline";
 
 export const ElementCallReactionEventType = "io.element.call.reaction";
 

src/reactions/useReactionsSender.tsx

@@ -18,7 +18,7 @@ import { type MatrixRTCSession } from "matrix-js-sdk/lib/matrixrtc";
 import { logger } from "matrix-js-sdk/lib/logger";
 
 import { useMatrixRTCSessionMemberships } from "../useMatrixRTCSessionMemberships";
-import { useClientState } from "../ClientContext";
+import { useHostBridge } from "../HostBridge";
 import { ElementCallReactionEventType, type ReactionOption } from ".";
 import { type CallViewModel } from "../state/CallViewModel/CallViewModel";
 import { useBehavior } from "../useBehavior";
@@ -54,9 +54,7 @@ export const ReactionsSenderProvider = ({
   vm: CallViewModel;
 }): JSX.Element => {
   const memberships = useMatrixRTCSessionMemberships(rtcSession);
-  const clientState = useClientState();
-  const supportsReactions =
-    clientState?.state === "valid" && clientState.supportedFeatures.reactions;
+  const { supportsReactions } = useHostBridge();
   const room = rtcSession.room;
   const myUserId = room.client.getUserId();
   const myDeviceId = room.client.getDeviceId();

src/room/CallEventAudioRenderer.tsx

@@ -8,18 +8,18 @@ Please see LICENSE in the repository root for full details.
 import { type ReactNode, useEffect } from "react";
 
 import { type CallViewModel } from "../state/CallViewModel/CallViewModel";
-import joinCallSoundMp3 from "../sound/join_call.mp3";
-import joinCallSoundOgg from "../sound/join_call.ogg";
-import leftCallSoundMp3 from "../sound/left_call.mp3";
-import leftCallSoundOgg from "../sound/left_call.ogg";
-import handSoundOgg from "../sound/raise_hand.ogg";
-import handSoundMp3 from "../sound/raise_hand.mp3";
-import screenShareStartedOgg from "../sound/screen_share_started.ogg";
-import screenShareStartedMp3 from "../sound/screen_share_started.mp3";
-import declineMp3 from "../sound/call_declined.mp3?url";
-import declineOgg from "../sound/call_declined.ogg?url";
-import timeoutMp3 from "../sound/call_timeout.mp3?url";
-import timeoutOgg from "../sound/call_timeout.ogg?url";
+import joinCallSoundMp3 from "../sound/join_call.mp3?url&no-inline";
+import joinCallSoundOgg from "../sound/join_call.ogg?url&no-inline";
+import leftCallSoundMp3 from "../sound/left_call.mp3?url&no-inline";
+import leftCallSoundOgg from "../sound/left_call.ogg?url&no-inline";
+import handSoundOgg from "../sound/raise_hand.ogg?url&no-inline";
+import handSoundMp3 from "../sound/raise_hand.mp3?url&no-inline";
+import screenShareStartedOgg from "../sound/screen_share_started.ogg?url&no-inline";
+import screenShareStartedMp3 from "../sound/screen_share_started.mp3?url&no-inline";
+import declineMp3 from "../sound/call_declined.mp3?url&no-inline";
+import declineOgg from "../sound/call_declined.ogg?url&no-inline";
+import timeoutMp3 from "../sound/call_timeout.mp3?url&no-inline";
+import timeoutOgg from "../sound/call_timeout.ogg?url&no-inline";
 import { useAudioContext } from "../useAudioContext";
 import { prefetchSounds } from "../soundUtils";
 import { useLatest } from "../useLatest";

src/room/InCallView.tsx

@@ -190,12 +190,9 @@ export const ActiveCall: FC<ActiveCallProps> = (props) => {
       props.matrixRoom,
       mediaDevices,
       props.muteStates,
-      props.e2eeSystem,
-      scope.behavior(observeElementSize$(rootElement)),
-      reactionsReader.raisedHands$,
-      reactionsReader.reactions$,
       {
         ...callViewModelOptionsFromParams(urlParams),
+        encryptionSystem: props.e2eeSystem,
         capture,
         backgroundEffectsState$,
         hostBridge,
@@ -205,7 +202,10 @@ export const ActiveCall: FC<ActiveCallProps> = (props) => {
           scope,
           props.rtcSession,
         ),
+        windowSize$: scope.behavior(observeElementSize$(rootElement)),
       },
+      reactionsReader.raisedHands$,
+      reactionsReader.reactions$,
     );
     setVm(vm);
 
@@ -822,9 +822,7 @@ export function rtcParticipationOptions(
   const session = config.matrix_rtc_session;
   return {
     sendNotificationType: urlParams.sendNotificationType,
-    applicationData: urlParams.callIntent
-      ? { "m.call.intent": urlParams.callIntent }
-      : undefined,
+    callIntent: urlParams.callIntent,
     timings: {
       syncDisconnectGracePeriodMs: config.sync_disconnect_grace_period_ms,
       networkErrorRetryMs: session.network_error_retry_ms,

src/room/RingingAudioRenderer.test.tsx

@@ -8,6 +8,7 @@ Please see LICENSE in the repository root for full details.
 import { expect, type MockedFunction, test, vi } from "vitest";
 import { act, render } from "@testing-library/react";
 import { BehaviorSubject } from "rxjs";
+import { RTC_CALL_INTENT_AUDIO } from "matrix-js-sdk/lib/matrixrtc";
 
 import { useAudioContext } from "../useAudioContext";
 import { createRingingMedia } from "../state/media/RingingMediaViewModel";
@@ -39,7 +40,7 @@ test("ringtone plays on loop while ringing", () => {
     userId: alice.userId,
     displayName$: constant("Alice"),
     mxcAvatarUrl$: constant(undefined),
-    intent: "audio",
+    intent: RTC_CALL_INTENT_AUDIO,
     pickupState$,
   });
 

src/room/RingingAudioRenderer.tsx

@@ -12,8 +12,8 @@ import { type RingingMediaViewModel } from "../state/media/RingingMediaViewModel
 import { useBehavior } from "../useBehavior";
 import { useInitial } from "../useInitial";
 import { prefetchSounds } from "../soundUtils";
-import ringtoneMp3 from "../sound/ringtone.mp3?url";
-import ringtoneOgg from "../sound/ringtone.ogg?url";
+import ringtoneMp3 from "../sound/ringtone.mp3?url&no-inline";
+import ringtoneOgg from "../sound/ringtone.ogg?url&no-inline";
 import { type UseAudioContext, useAudioContext } from "../useAudioContext";
 import { useLatest } from "../useLatest";
 

src/room/RoomPage.test.tsx

@@ -0,0 +1,101 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { afterEach, expect, test, vi } from "vitest";
+import { render, screen } from "@testing-library/react";
+import { MemoryRouter } from "react-router-dom";
+import { type MatrixClient } from "matrix-js-sdk";
+import { BehaviorSubject } from "rxjs";
+
+import { RoomPage } from "./RoomPage";
+import { ClientContextProvider } from "../ClientContext";
+import { type ClientSessionState } from "../state/ClientSession";
+import { computeUrlParams, UrlParamsProvider } from "../UrlParams";
+import { useLoadGroupCall } from "./useLoadGroupCall";
+
+vi.mock("./useLoadGroupCall", () => ({
+  useLoadGroupCall: vi.fn(() => ({ kind: "loading" })),
+  CallTerminatedMessage: class extends Error {},
+}));
+vi.mock("./useRoomName", () => ({ useRoomName: () => null }));
+vi.mock("../profile/useProfile", () => ({ useProfile: () => ({}) }));
+vi.mock("../auth/useRegisterPasswordlessUser", () => ({
+  useRegisterPasswordlessUser: () => ({ registerPasswordlessUser }),
+}));
+vi.mock("./RoomAuthView", () => ({
+  RoomAuthView: () => <span>room auth view</span>,
+}));
+vi.mock("../home/HomePage", () => ({
+  HomePage: () => <span>home page</span>,
+}));
+vi.mock("./CallView", () => ({
+  CallView: ({ isPasswordlessUser }: { isPasswordlessUser: boolean }) => (
+    <span>call view, passwordless: {String(isPasswordlessUser)}</span>
+  ),
+}));
+vi.mock("./KnockLobbyView", () => ({ KnockLobbyView: () => null }));
+
+const registerPasswordlessUser = vi.fn().mockResolvedValue(undefined);
+
+afterEach(() => vi.clearAllMocks());
+
+test("waits for the session to be restored", () => {
+  renderRoom({ state: "loading" }, "/call");
+  expect(screen.getByRole("heading", { name: "Loading…" })).toBeVisible();
+});
+
+test("asks a signed-out user to join as a guest", () => {
+  renderRoom({ state: "signedOut" }, "/call");
+  expect(screen.getByText("room auth view")).toBeVisible();
+  expect(registerPasswordlessUser).not.toHaveBeenCalled();
+});
+
+test("registers a passwordless user when the URL names one", () => {
+  renderRoom({ state: "signedOut" }, "/call", "Alice");
+  expect(registerPasswordlessUser).toHaveBeenCalledWith("Alice");
+});
+
+test("falls back to the home page without a room", () => {
+  renderRoom(signedIn(false), "/");
+  expect(screen.getByText("home page")).toBeVisible();
+});
+
+test("tells the call whether its user is passwordless", () => {
+  vi.mocked(useLoadGroupCall).mockReturnValue({
+    kind: "loaded",
+    rtcSession: { room: {} },
+  } as unknown as ReturnType<typeof useLoadGroupCall>);
+
+  renderRoom(signedIn(true), "/call");
+  expect(screen.getByText("call view, passwordless: true")).toBeVisible();
+});
+
+function signedIn(passwordlessUser: boolean): ClientSessionState {
+  return {
+    state: "signedIn",
+    client: { getUserId: () => "@alice:example.org" } as MatrixClient,
+    passwordlessUser,
+  };
+}
+
+function renderRoom(
+  state: ClientSessionState,
+  path: string,
+  displayName: string | null = null,
+): void {
+  render(
+    <MemoryRouter initialEntries={[path]}>
+      <UrlParamsProvider value={{ ...computeUrlParams(), displayName }}>
+        <ClientContextProvider
+          value={{ state$: new BehaviorSubject<ClientSessionState>(state) }}
+        >
+          <RoomPage />
+        </ClientContextProvider>
+      </UrlParamsProvider>
+    </MemoryRouter>,
+  );
+}

src/room/RoomPage.tsx

@@ -12,7 +12,7 @@ import { logger } from "matrix-js-sdk/lib/logger";
 import { Trans, useTranslation } from "react-i18next";
 import { UnknownSolidIcon } from "@vector-im/compound-design-tokens/assets/web/icons";
 
-import { useClientLegacy } from "../ClientContext";
+import { useClient, useClientSessionState } from "../ClientContext";
 import { ErrorPage, FullScreenView, LoadingPage } from "../FullScreenView";
 import { RoomAuthView } from "./RoomAuthView";
 import { CallView } from "./CallView";
@@ -42,8 +42,12 @@ export const RoomPage: FC = (): ReactNode => {
   const { registerPasswordlessUser } = useRegisterPasswordlessUser();
   const [isRegistering, setIsRegistering] = useState(false);
 
-  const { loading, authenticated, client, error, passwordlessUser } =
-    useClientLegacy();
+  const { client } = useClient();
+  const session = useClientSessionState();
+  const loading = session.state === "loading";
+  const passwordlessUser =
+    session.state === "signedIn" && session.passwordlessUser;
+  const authenticated = client !== undefined;
   const { avatarUrl, displayName: userDisplayName } = useProfile(client);
 
   const groupCallState = useLoadGroupCall(client, roomIdOrAlias, viaServers);
@@ -184,7 +188,6 @@ export const RoomPage: FC = (): ReactNode => {
   };
 
   if (loading || isRegistering) return <LoadingPage />;
-  if (error) return <ErrorPage error={error} />;
   if (!client) return <RoomAuthView />;
   // TODO: This doesn't belong here, the app routes need to be reworked
   if (!roomIdOrAlias) return <HomePage />;

src/room/VideoPreview.test.tsx

@@ -7,12 +7,9 @@ Please see LICENSE in the repository root for full details.
 
 import { expect, describe, it, beforeAll } from "vitest";
 import { render } from "@testing-library/react";
-import { constant } from "@element-hq/matrixrtc-sdk";
 
 import { type MatrixInfo, VideoPreview } from "./VideoPreview";
 import { E2eeType } from "../e2ee/e2eeType";
-import { mockVideoTrack } from "../utils/test";
-import styles from "./VideoPreview.module.css";
 
 describe("VideoPreview", () => {
   const matrixInfo: MatrixInfo = {
@@ -63,18 +60,4 @@ describe("VideoPreview", () => {
     );
     expect(queryByRole("status")).toHaveTextContent("Video loading...");
   });
-
-  it("mirrors a camera that doesn't say which way it faces", () => {
-    const { container } = render(
-      <VideoPreview
-        matrixInfo={matrixInfo}
-        videoEnabled
-        videoTrack={mockVideoTrack({ facingMode$: constant(undefined) })}
-        children={<></>}
-      />,
-    );
-    expect(
-      container.querySelector("video")!.classList.contains(styles.mirror),
-    ).toBe(true);
-  });
 });

src/room/VideoPreview.tsx

@@ -16,7 +16,6 @@ import styles from "./VideoPreview.module.css";
 import { type EncryptionSystem } from "../e2ee/sharedKeyManagement";
 import videoPlaceholder from "../graphics/video-placeholder.gif";
 import { useBehavior } from "../useBehavior";
-import { mirrors } from "../utils/media";
 
 const noFacingMode = constant(undefined);
 
@@ -65,7 +64,7 @@ export const VideoPreview: FC<Props> = ({
   return (
     <div className={classNames(styles.preview)} ref={previewRef}>
       <video
-        className={mirrors(facingMode) ? styles.mirror : undefined}
+        className={facingMode === "user" ? styles.mirror : undefined}
         ref={videoEl}
         muted
         playsInline

src/room/__snapshots__/LobbyView.test.tsx.snap

@@ -47,7 +47,6 @@ exports[`LobbyView > renders with AppBar android 1`] = `
         class="_preview_dd2178"
       >
         <video
-          class="_mirror_dd2178"
           disablepictureinpicture=""
           playsinline=""
           poster="/src/graphics/video-placeholder.gif"
@@ -280,7 +279,6 @@ exports[`LobbyView > renders with AppBar ios 1`] = `
         class="_preview_dd2178"
       >
         <video
-          class="_mirror_dd2178"
           disablepictureinpicture=""
           playsinline=""
           poster="/src/graphics/video-placeholder.gif"
@@ -560,7 +558,6 @@ exports[`LobbyView > renders with header and participant count 1`] = `
         class="_preview_dd2178"
       >
         <video
-          class="_mirror_dd2178"
           disablepictureinpicture=""
           playsinline=""
           poster="/src/graphics/video-placeholder.gif"

src/settings/useSubmitRageshake.test.tsx

@@ -20,6 +20,7 @@ import { type MatrixClient } from "matrix-js-sdk/lib/client";
 
 import { useSubmitRageshake, getRageshakeSubmitUrl } from "./submit-rageshake";
 import { ClientContextProvider } from "../ClientContext";
+import { hostClientSession } from "../state/ClientSession";
 import { getUrlParams } from "../UrlParams";
 import { mockConfig } from "../utils/test";
 import { DEFAULT_CONFIG } from "../config/ConfigOptions";
@@ -74,22 +75,7 @@ function renderWithMockClient(
   } as unknown as MatrixClient);
 
   render(
-    <ClientContextProvider
-      value={{
-        state: "valid",
-        disconnected: false,
-        supportedFeatures: {
-          reactions: true,
-        },
-        setClient: vi.fn(),
-        authenticated: {
-          client,
-          isPasswordlessUser: true,
-          changePassword: vi.fn(),
-          logout: vi.fn(),
-        },
-      }}
-    >
+    <ClientContextProvider value={hostClientSession(client)}>
       <TestComponent
         sendLogs={sendLogs}
         getRageshakeSubmitUrl={getRageshakeSubmitUrl}

src/soundUtils.test.ts

@@ -34,23 +34,6 @@ describe("prefetchSounds", () => {
     expect(bytesOf(sounds.beep)).toEqual([1, 2, 3]);
   });
 
-  it("decodes base64 data: URLs without fetching them", async () => {
-    // "OggS" — the bytes 0x4f 0x67 0x67 0x53
-    const sounds = await prefetchSounds({
-      beep: { ogg: "data:audio/ogg;base64,T2dnUw==" },
-    });
-    expect(fetchSpy).not.toHaveBeenCalled();
-    expect(bytesOf(sounds.beep)).toEqual([0x4f, 0x67, 0x67, 0x53]);
-  });
-
-  it("leaves out a sound with a percent-encoded data: URL", async () => {
-    const sounds = await prefetchSounds({
-      beep: { ogg: "data:audio/ogg,Ogg%53" },
-    });
-    expect(fetchSpy).not.toHaveBeenCalled();
-    expect(sounds).toEqual({});
-  });
-
   it("leaves out a sound whose response is not okay", async () => {
     fetchSpy.mockResolvedValue(new Response(null, { status: 404 }));
     const sounds = await prefetchSounds({
@@ -60,18 +43,16 @@ describe("prefetchSounds", () => {
   });
 
   it("leaves out a sound that fails to load, keeping the others", async () => {
-    fetchSpy.mockRejectedValue(new TypeError("Failed to fetch"));
+    // Fetched in the order given
+    fetchSpy
+      .mockRejectedValueOnce(new TypeError("Failed to fetch"))
+      .mockResolvedValueOnce(
+        new Response(new Uint8Array([1, 2, 3]), { status: 200 }),
+      );
     const sounds = await prefetchSounds({
       beep: { ogg: "https://example.org/beep.ogg" },
-      boop: { ogg: "data:audio/ogg;base64,T2dnUw==" },
+      boop: { ogg: "https://example.org/boop.ogg" },
     });
     expect(Object.keys(sounds)).toEqual(["boop"]);
   });
-
-  it("leaves out a sound with a malformed data: URL", async () => {
-    const sounds = await prefetchSounds({
-      beep: { ogg: "data:audio/ogg;base64" },
-    });
-    expect(sounds).toEqual({});
-  });
 });

src/soundUtils.ts

@@ -32,38 +32,12 @@ function getPreferredAudioFormat(): "ogg" | "mp3" {
 
 const preferredFormat = getPreferredAudioFormat();
 
-/**
- * Decode a `data:` URL into the bytes it carries.
- *
- * The component build inlines the sound files as `data:` URLs. Those could be
- * `fetch`ed like any other URL, but that fetch is subject to the host page's
- * Content Security Policy, and `connect-src` lists rarely allow `data:` (a `*`
- * source does not cover it). Reading the bytes out of the URL directly needs no
- * network access, so no policy can stop it.
- * @param url The `data:` URL to decode.
- * @returns The decoded bytes.
- */
-function decodeDataUrl(url: string): ArrayBuffer {
-  const separator = url.indexOf(",");
-  if (!url.startsWith("data:") || separator === -1)
-    throw new Error("Not a valid data: URL");
-  const header = url.slice("data:".length, separator);
-  // Vite only percent-encodes SVGs; every other inlined asset is base64.
-  if (!header.split(";").includes("base64"))
-    throw new Error("Only base64 data: URLs are supported");
-  // `decoded` is a binary string: one char per byte
-  const decoded = atob(url.slice(separator + 1));
-  const bytes = Uint8Array.from(decoded, (c) => c.charCodeAt(0));
-  return bytes.buffer;
-}
-
 /**
  * Load the bytes of a single sound file.
- * @param url Where the sound is: an ordinary URL to fetch, or a `data:` URL.
+ * @param url Where the sound is.
  * @returns The bytes, or null if the sound could not be loaded.
  */
 async function loadSound(url: string): Promise<ArrayBuffer | null> {
-  if (url.startsWith("data:")) return decodeDataUrl(url);
   const response = await fetch(url);
   if (isFailure(response)) return null;
   return await response.arrayBuffer();

src/state/AndroidControlledAudioOutput.test.ts

@@ -7,7 +7,11 @@ Please see LICENSE in the repository root for full details.
 
 import { it, vi, expect, beforeEach, afterEach, describe } from "vitest";
 import { firstValueFrom, of, Subject, take, toArray } from "rxjs";
-import { type RTCCallIntent } from "matrix-js-sdk/lib/matrixrtc";
+import {
+  RTC_CALL_INTENT_AUDIO,
+  RTC_CALL_INTENT_VIDEO,
+  type RTCCallIntent,
+} from "matrix-js-sdk/lib/matrixrtc";
 
 import { AndroidControlledAudioOutput } from "./AndroidControlledAudioOutput.ts";
 import type { Controls, OutputDevice } from "../controls";
@@ -117,7 +121,7 @@ describe("Default selection", () => {
     const controlledAudioOutput = new AndroidControlledAudioOutput(
       of(BASE_DEVICE_LIST),
       testScope,
-      "video",
+      RTC_CALL_INTENT_VIDEO,
       mockControls,
     );
 
@@ -142,7 +146,7 @@ describe("Default selection", () => {
     const controlledAudioOutput = new AndroidControlledAudioOutput(
       of(BASE_DEVICE_LIST),
       testScope,
-      "audio",
+      RTC_CALL_INTENT_AUDIO,
       mockControls,
     );
 
@@ -163,7 +167,7 @@ describe("Default selection", () => {
     });
   });
 
-  ["audio", "video"].forEach((callIntent) => {
+  [RTC_CALL_INTENT_AUDIO, RTC_CALL_INTENT_VIDEO].forEach((callIntent) => {
     it(`Default to BT headset for ${callIntent} calls if present`, async () => {
       const controlledAudioOutput = new AndroidControlledAudioOutput(
         of(BT_HEADSET_BASE_DEVICE_LIST),
@@ -190,7 +194,7 @@ describe("Default selection", () => {
     });
   });
 
-  ["audio", "video"].forEach((callIntent) => {
+  [RTC_CALL_INTENT_AUDIO, RTC_CALL_INTENT_VIDEO].forEach((callIntent) => {
     it(`Default to wired headset for ${callIntent} calls if present`, async () => {
       const controlledAudioOutput = new AndroidControlledAudioOutput(
         of(WIRED_HEADSET_BASE_DEVICE_LIST),
@@ -300,7 +304,7 @@ describe("Test select a device", () => {
           b: BT_HEADSET_BASE_DEVICE_LIST,
         }),
         testScope,
-        "audio",
+        RTC_CALL_INTENT_AUDIO,
         mockControls,
       );
 
@@ -340,7 +344,7 @@ describe("Test select a device", () => {
           c: BASE_DEVICE_LIST,
         }),
         testScope,
-        "audio",
+        RTC_CALL_INTENT_AUDIO,
         mockControls,
       );
 
@@ -393,7 +397,7 @@ describe("Available device changes", () => {
   });
 
   it("When a BT headset is added, control should switch to use it", () => {
-    createAudioControlledOutput("video");
+    createAudioControlledOutput(RTC_CALL_INTENT_VIDEO);
 
     // Emit the base device list, the speaker should be selected
     availableSource$.next(BASE_DEVICE_LIST);
@@ -419,7 +423,9 @@ describe("Available device changes", () => {
 
   // Android does not set `isExternalHeadset` to true for wired headphones, so we can't test this case.'
   it.skip("When a wired headset is added, control should switch to use it", async () => {
-    const controlledAudioOutput = createAudioControlledOutput("video");
+    const controlledAudioOutput = createAudioControlledOutput(
+      RTC_CALL_INTENT_VIDEO,
+    );
 
     // Emit the base device list, the speaker should be selected
     availableSource$.next(BASE_DEVICE_LIST);
@@ -446,7 +452,7 @@ describe("Available device changes", () => {
   });
 
   it("When the active bt headset is removed on audio call, control should switch to earpiece", () => {
-    createAudioControlledOutput("audio");
+    createAudioControlledOutput(RTC_CALL_INTENT_AUDIO);
 
     // Emit the BT headset device list, the BT headset should be selected
     availableSource$.next(BT_HEADSET_BASE_DEVICE_LIST);
@@ -472,7 +478,7 @@ describe("Available device changes", () => {
   });
 
   it("When the active bt headset is removed on video call, control should switch to speaker", () => {
-    createAudioControlledOutput("video");
+    createAudioControlledOutput(RTC_CALL_INTENT_VIDEO);
 
     availableSource$.next(BT_HEADSET_BASE_DEVICE_LIST);
 
@@ -497,7 +503,7 @@ describe("Available device changes", () => {
   });
 
   it("Do not repeatidly set the same device", () => {
-    createAudioControlledOutput("video");
+    createAudioControlledOutput(RTC_CALL_INTENT_VIDEO);
 
     availableSource$.next(BT_HEADSET_BASE_DEVICE_LIST);
     availableSource$.next(BT_HEADSET_BASE_DEVICE_LIST);

src/state/AndroidControlledAudioOutput.ts

@@ -22,7 +22,10 @@ import {
   type SelectedAudioOutputDevice,
 } from "./MediaDevices.ts";
 import type { ObservableScope } from "./ObservableScope.ts";
-import type { RTCCallIntent } from "matrix-js-sdk/lib/matrixrtc";
+import {
+  RTC_CALL_INTENT_AUDIO,
+  type RTCCallIntent,
+} from "matrix-js-sdk/lib/matrixrtc";
 import { type Controls, type OutputDevice } from "../controls.ts";
 import { type Behavior } from "./Behavior.ts";
 
@@ -102,7 +105,7 @@ export class AndroidControlledAudioOutput implements MediaDevice<
    * @constructor
    * @param controlledDevices$ - The list of available output devices coming from the hosting application, ordered by preference order (most preferred first).
    * @param scope - The ObservableScope to create the Behaviors in.
-   * @param initialIntent - The initial call intent (e.g. "audio" or "video") that can be used to determine the default audio routing (e.g. default to earpiece for audio calls and speaker for video calls).
+   * @param initialIntent - The initial call intent (e.g. "m.audio" or "m.video") that can be used to determine the default audio routing (e.g. default to earpiece for audio calls and speaker for video calls).
    * @param controls - The controls provided by the hosting application to control the audio routing and notify of user actions.
    */
   public constructor(
@@ -316,7 +319,7 @@ export class AndroidControlledAudioOutput implements MediaDevice<
     this.logger.debug(
       `Android routing logic intent: ${this.initialIntent} finding best default...`,
     );
-    if (this.initialIntent === "audio") {
+    if (this.initialIntent === RTC_CALL_INTENT_AUDIO) {
       const systemProposed = available[0];
       // If no headset is connected, android will route to the speaker by default,
       // but for a voice call we want to route to the earpiece instead,

src/state/AppViewModel.ts

@@ -5,6 +5,7 @@ SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
 Please see LICENSE in the repository root for full details.
 */
 
+import { type ClientManager, type ClientSession } from "./ClientSession";
 import { type AudioOutputOptions, MediaDevices } from "./MediaDevices";
 import { type ObservableScope } from "./ObservableScope";
 import { createAppBackgroundEffects } from "../tracks/BackgroundEffectsContext";
@@ -22,8 +23,14 @@ export class AppViewModel {
   // TODO: Move more application logic here. The CallViewModel, at the very
   // least, ought to be accessible from this object.
 
+  /**
+   * @param clientSession Where the client comes from. SPA js-sdk, EW host, widget
+   */
   public constructor(
     private readonly scope: ObservableScope,
     private readonly audioOutputOptions: AudioOutputOptions,
+    public readonly clientSession: ClientSession,
+    /** Null where the session is a host's and not ours to manage. */
+    public readonly clientManager: ClientManager | null,
   ) {}
 }

src/state/BackgroundEffects.ts

@@ -57,8 +57,7 @@ export interface BackgroundEffectsOptions {
   supported: boolean;
   /** The effect chosen, as the setting stores it. */
   effect$: Behavior<string>;
-  /** Saves the chosen effect. Used to reset the choice to "none" when the
-   * chosen effect can't run here. */
+  /** Stores a choice, to forget one that can't be honoured. */
   setEffect: (id: EffectId) => void;
   /** The backgrounds the device keeps, undefined until it has said. */
   added$: Behavior<AddedBackground[] | undefined>;

src/state/CallViewModel/CallNotificationLifecycle.test.ts

@@ -12,7 +12,11 @@ import {
   MatrixEvent,
   type Room,
 } from "matrix-js-sdk";
-import { type RTCCallIntent } from "matrix-js-sdk/lib/matrixrtc";
+import {
+  RTC_CALL_INTENT_AUDIO,
+  RTC_CALL_INTENT_VIDEO,
+  type RTCCallIntent,
+} from "matrix-js-sdk/lib/matrixrtc";
 import { map, mergeMap, NEVER, type Observable, startWith } from "rxjs";
 
 import { withTestScheduler } from "../../utils/test";
@@ -33,10 +37,12 @@ function mockRingEvent(
   eventId: string,
   lifetimeMs: number | undefined,
   sender = local.userId,
+  legacyIntent?: string,
 ): CallNotificationWrapper {
   return {
     event_id: eventId,
     ...(lifetimeMs === undefined ? {} : { lifetime: lifetimeMs }),
+    ...(legacyIntent === undefined ? {} : { "m.call.intent": legacyIntent }),
     notification_type: "ring",
     sender,
   } as unknown as CallNotificationWrapper;
@@ -128,7 +134,25 @@ test("ring attempt times out after nobody joins", () => {
     });
 
     expectObservable(summarizeRingAttempts$(ringAttempts$)).toBe("-a 29ms A", {
-      a: { intent: "audio", recipient: alice.userId },
+      a: { intent: RTC_CALL_INTENT_AUDIO, recipient: alice.userId },
+      A: { outcome: "timeout" },
+    });
+  });
+});
+
+test("ring attempt maps the legacy intent on the notification to its stable value", () => {
+  withTestScheduler(({ scope, expectObservable, hot }) => {
+    const { ringAttempts$ } = createCallNotificationLifecycle$({
+      scope,
+      ...defaultProps,
+      memberUserIds$: constant<string[]>([]),
+      sentCallNotification$: hot("-a", {
+        a: mockRingEvent("$notif1", 30, local.userId, "video"),
+      }),
+    });
+
+    expectObservable(summarizeRingAttempts$(ringAttempts$)).toBe("-a 29ms A", {
+      a: { intent: RTC_CALL_INTENT_VIDEO, recipient: alice.userId },
       A: { outcome: "timeout" },
     });
   });
@@ -148,7 +172,7 @@ test("ring attempt is accepted once recipient joins", () => {
     });
 
     expectObservable(summarizeRingAttempts$(ringAttempts$)).toBe("-aA", {
-      a: { intent: "audio", recipient: alice.userId },
+      a: { intent: RTC_CALL_INTENT_AUDIO, recipient: alice.userId },
       A: { outcome: "accept" },
     });
   });
@@ -166,7 +190,7 @@ test("ring attempt is immediately accepted if recipient is already joined", () =
     });
 
     expectObservable(summarizeRingAttempts$(ringAttempts$)).toBe("-(aA)", {
-      a: { intent: "audio", recipient: alice.userId },
+      a: { intent: RTC_CALL_INTENT_AUDIO, recipient: alice.userId },
       A: { outcome: "accept" },
     });
   });
@@ -201,7 +225,7 @@ test("ring attempt can be declined", () => {
     });
 
     expectObservable(summarizeRingAttempts$(ringAttempts$)).toBe("-aA", {
-      a: { intent: "audio", recipient: alice.userId },
+      a: { intent: RTC_CALL_INTENT_AUDIO, recipient: alice.userId },
       A: { outcome: "decline" },
     });
   });
@@ -236,7 +260,7 @@ test("ring attempt times out if recipient declines too late", () => {
     });
 
     expectObservable(summarizeRingAttempts$(ringAttempts$)).toBe("-a 29ms A", {
-      a: { intent: "audio", recipient: alice.userId },
+      a: { intent: RTC_CALL_INTENT_AUDIO, recipient: alice.userId },
       A: { outcome: "timeout" },
     });
   });
@@ -271,7 +295,7 @@ test("decline event relating to wrong event is ignored (times out)", () => {
     });
 
     expectObservable(summarizeRingAttempts$(ringAttempts$)).toBe("-a 29ms A", {
-      a: { intent: "audio", recipient: alice.userId },
+      a: { intent: RTC_CALL_INTENT_AUDIO, recipient: alice.userId },
       A: { outcome: "timeout" },
     });
   });
@@ -306,7 +330,7 @@ test("decline event from wrong sender is ignored (times out)", () => {
     });
 
     expectObservable(summarizeRingAttempts$(ringAttempts$)).toBe("-a 29ms A", {
-      a: { intent: "audio", recipient: alice.userId },
+      a: { intent: RTC_CALL_INTENT_AUDIO, recipient: alice.userId },
       A: { outcome: "timeout" },
     });
   });

src/state/CallViewModel/CallNotificationLifecycle.ts

@@ -9,7 +9,9 @@ import {
   type IRTCNotificationContent,
   type MatrixRTCSession,
   MatrixRTCSessionEvent,
+  RTC_CALL_INTENT_AUDIO,
   type RTCCallIntent,
+  toStableCallIntent,
 } from "matrix-js-sdk/lib/matrixrtc";
 import {
   filter,
@@ -155,7 +157,10 @@ export function createCallNotificationLifecycle$({
         );
 
         return of({
-          intent: notificationEvent["m.call.intent"] ?? "audio",
+          // The notification still carries the legacy intent values
+          intent:
+            toStableCallIntent(notificationEvent["m.call.intent"]) ??
+            RTC_CALL_INTENT_AUDIO,
           recipient,
           outcome$: race(timeout$, accept$, decline$).pipe(
             take(1),

src/state/CallViewModel/CallViewModel.test.ts

@@ -21,6 +21,7 @@ import {
   type CallMembership,
   type IRTCNotificationContent,
   MatrixRTCSessionEvent,
+  RTC_CALL_INTENT_AUDIO,
 } from "matrix-js-sdk/lib/matrixrtc";
 import { deepCompare } from "matrix-js-sdk/lib/utils";
 
@@ -35,6 +36,7 @@ import {
   mockRtcMembership,
   testScope,
 } from "../../utils/test.ts";
+import { E2eeType } from "../../e2ee/e2eeType.ts";
 import {
   alice,
   aliceId,
@@ -1464,6 +1466,7 @@ describe.each(modes)("CallViewModel (%s mode)", (mode) => {
         },
         {
           autoLeaveWhenOthersLeft: true,
+          encryptionSystem: { kind: E2eeType.PER_PARTICIPANT },
         },
       );
     });
@@ -1481,6 +1484,7 @@ describe.each(modes)("CallViewModel (%s mode)", (mode) => {
         },
         {
           autoLeaveWhenOthersLeft: true,
+          encryptionSystem: { kind: E2eeType.PER_PARTICIPANT },
         },
       );
     });
@@ -1498,6 +1502,7 @@ describe.each(modes)("CallViewModel (%s mode)", (mode) => {
         },
         {
           autoLeaveWhenOthersLeft: false,
+          encryptionSystem: { kind: E2eeType.PER_PARTICIPANT },
         },
       );
     });
@@ -1527,6 +1532,7 @@ describe.each(modes)("CallViewModel (%s mode)", (mode) => {
         },
         {
           autoLeaveWhenOthersLeft: true,
+          encryptionSystem: { kind: E2eeType.PER_PARTICIPANT },
         },
       );
     });
@@ -1554,7 +1560,7 @@ describe.each(modes)("CallViewModel (%s mode)", (mode) => {
             b: expect.objectContaining({
               type: "ringing",
               userId: alice.userId,
-              intent: "audio",
+              intent: RTC_CALL_INTENT_AUDIO,
             }),
           });
           // Layout should show placeholder media for the participant we're
@@ -1600,7 +1606,7 @@ describe.each(modes)("CallViewModel (%s mode)", (mode) => {
             b: expect.objectContaining({
               type: "ringing",
               userId: alice.userId,
-              intent: "audio",
+              intent: RTC_CALL_INTENT_AUDIO,
             }),
           });
           // Layout should show placeholder media for the participant we're