Remove a background of one's own

- A cross on the tile's top-right corner removes an added background,
  critical-coloured at rest and named by its tooltip, as design draws it.
  The one in force offers none, since taking it away would leave nothing
  chosen; the view model refuses it too.
- The cross sits beside the item rather than in it, which would take the
  press first and choose the tile, and isn't a control of its own, so the
  menu keeps one keyboard model: Delete or Backspace on the tile does the
  same, and the tile says so with aria-keyshortcuts.
- Removed from IndexedDB and its picture released. End to end on
  Chromium and Firefox, a background removed by Delete is still gone
  after a reload.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

playwright/background-effects.spec.ts

@@ -326,6 +326,33 @@ test.describe("a background of one's own", () => {
     await addImage(page, red);
     await expect(mine).toBeVisible();
   });
+
+  test("a removed image stays removed", async ({ page }) => {
+    test.setTimeout(120_000);
+    await page.goto("/");
+    await SpaHelpers.createCall(
+      page,
+      "Removing user",
+      "Own background removed",
+    );
+    await addImage(page, await redImage(page));
+    const mine = page
+      .getByRole("group", { name: "Background effects" })
+      .getByRole("menuitemradio", { name: "Background 3" });
+    await expect(mine).toHaveAttribute("aria-keyshortcuts", "Delete");
+    await mine.focus();
+    await page.keyboard.press("Delete");
+    await expect(mine).toHaveCount(0);
+
+    await page.reload();
+    await expect(page.getByTestId("lobby_joinCall")).toBeVisible();
+    await page.getByRole("button", { name: "Camera", exact: true }).click();
+    await expect(
+      page.getByRole("group", { name: "Background effects" }),
+    ).toBeVisible();
+    await expect(mine).toHaveCount(0);
+    expect(await keptImages(page)).toEqual([]);
+  });
 });
 
 test.describe("what can be added", () => {

src/components/BackgroundEffectGrid.module.css

@@ -90,3 +90,42 @@ Please see LICENSE in the repository root for full details.
   text-align: center;
   overflow-wrap: anywhere;
 }
+
+.removable {
+  position: relative;
+  display: flex;
+  min-inline-size: 0;
+}
+
+.removable > .tile {
+  flex: 1;
+}
+
+/* Clear of the target for choosing the tile. */
+.remove {
+  position: absolute;
+  inset-block-start: 0;
+  inset-inline-end: 0;
+  translate: 20% -20%;
+  display: none;
+  align-items: center;
+  justify-content: center;
+  inline-size: 28px;
+  block-size: 28px;
+  border-radius: 50%;
+  background: var(--cpd-color-bg-canvas-default);
+  color: var(--cpd-color-icon-critical-primary);
+  box-shadow: 0 1.2px 2.4px 0 rgb(0 0 0 / 15%);
+  cursor: pointer;
+}
+
+.remove:hover {
+  background: var(--cpd-color-bg-critical-subtle-hovered);
+  box-shadow: 0 0 0 var(--cpd-border-width-1)
+    var(--cpd-color-border-critical-subtle);
+}
+
+.removable:hover .remove,
+.removable:focus-within .remove {
+  display: flex;
+}

src/components/BackgroundEffectGrid.tsx

@@ -5,13 +5,19 @@ SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
 Please see LICENSE in the repository root for full details.
 */
 
-import { type FC, type ReactNode, type ReactElement } from "react";
+import {
+  type FC,
+  type KeyboardEvent,
+  type ReactNode,
+  type ReactElement,
+} from "react";
 import { VisuallyHidden } from "@radix-ui/react-visually-hidden";
-import { InlineSpinner, MenuItem } from "@vector-im/compound-web";
+import { InlineSpinner, MenuItem, Tooltip } from "@vector-im/compound-web";
 import {
   BlockIcon,
   BlurIcon,
   CheckCircleSolidIcon,
+  CloseIcon,
   PlusIcon,
 } from "@vector-im/compound-design-tokens/assets/web/icons";
 
@@ -25,6 +31,8 @@ export interface BackgroundEffectOption {
   kind: "none" | "blur" | "image";
   /** For kind "image". */
   imageUrl?: string;
+  /** Whether it is the user's to remove. */
+  removable?: boolean;
 }
 
 interface Props {
@@ -42,6 +50,9 @@ 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, never the one in force. Omit to offer none. */
+  onRemove?: (id: string) => void;
+  removeLabel?: string;
 }
 
 /**
@@ -58,6 +69,8 @@ export const BackgroundEffectGrid: FC<Props> = ({
   describedBy,
   onAdd,
   addLabel,
+  onRemove,
+  removeLabel,
 }) => {
   const choose = (id: string): void => {
     if (id !== selected) onSelect?.(id);
@@ -65,7 +78,29 @@ export const BackgroundEffectGrid: FC<Props> = ({
   const tiles = effects.map((effect) => {
     const checked = effect.id === selected;
     const disabled = onSelect === undefined && effect.kind !== "none";
-    return (
+    const remove =
+      effect.removable && !checked && onRemove !== undefined
+        ? (): void => onRemove(effect.id)
+        : undefined;
+    const removeProps =
+      remove === undefined
+        ? {}
+        : {
+            "aria-keyshortcuts": "Delete",
+            onKeyDown: (e: KeyboardEvent): void => {
+              if (e.key !== "Delete" && e.key !== "Backspace") return;
+              e.preventDefault();
+              remove();
+            },
+          };
+    const content = (
+      <TileContent
+        effect={effect}
+        checked={checked}
+        settling={checked && settling}
+      />
+    );
+    const tile = (
       <MenuItem
         key={effect.id}
         role="menuitemradio"
@@ -87,17 +122,37 @@ export const BackgroundEffectGrid: FC<Props> = ({
                 choose(effect.id);
               }
         }
+        {...removeProps}
       >
-        <TileContent
+        {content}
-          effect={effect}
-          checked={checked}
-          settling={checked && settling}
-        />
       </MenuItem>
     );
+    if (remove === undefined) return tile;
+    // Beside the item, not in it: inside, the item takes the press first and
+    // the tile is chosen instead.
+    return (
+      <div key={effect.id} className={styles.removable}>
+        {tile}
+        <Tooltip label={removeLabel ?? ""}>
+          {/* Not a control of its own, so the menu keeps one keyboard model:
+              the keyboard reaches the same action through Delete. */}
+          <span aria-hidden className={styles.remove} onClick={remove}>
+            <CloseIcon width={20} height={20} />
+          </span>
+        </Tooltip>
+      </div>
+    );
   });
 
   // A command rather than a choice, so an item beside the radios.
+  const addContent = (
+    <>
+      <span aria-hidden className={styles.swatch}>
+        <PlusIcon width={24} height={24} />
+      </span>
+      <VisuallyHidden>{addLabel}</VisuallyHidden>
+    </>
+  );
   const addTile =
     onAdd === undefined ? null : (
       <MenuItem
@@ -109,10 +164,7 @@ export const BackgroundEffectGrid: FC<Props> = ({
           onAdd();
         }}
       >
-        <span aria-hidden className={styles.swatch}>
+        {addContent}
-          <PlusIcon width={24} height={24} />
-        </span>
-        <VisuallyHidden>{addLabel}</VisuallyHidden>
       </MenuItem>
     );
 

src/components/CallFooter.stories.tsx

@@ -127,18 +127,20 @@ export const Default: Story = {
     selectBackgroundEffect: fn(),
     backgroundEffect: "blur",
     backgroundEffects: [
-      { id: "none", kind: "none" },
+      { id: "none", kind: "none", removable: false },
-      { id: "blur", kind: "blur" },
+      { 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(),
     hangup: fn(),
     buttonSize: "lg",
     showFooter: true,

src/components/CallFooter.tsx

@@ -45,6 +45,8 @@ export interface BackgroundEffectChoice {
   id: string;
   kind: "none" | "blur" | "image";
   imageUrl?: string;
+  /** One the user added, which they can take away again. */
+  removable: boolean;
 }
 
 export interface AudioOutputSwitcher {
@@ -75,6 +77,8 @@ export interface FooterActions {
   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;
@@ -186,6 +190,7 @@ export const CallFooter: FC<FooterProps> = ({
   const backgroundEffectNotice = useBehavior(vm.backgroundEffectNotice$);
   const backgroundEffectSettling = useBehavior(vm.backgroundEffectSettling$);
   const addBackgroundImage = useBehavior(vm.addBackgroundImage$);
+  const removeBackgroundEffect = useBehavior(vm.removeBackgroundEffect$);
   const refusal = useBehavior(vm.backgroundImageRefusal$);
   const refusalMessage = useMemo(() => {
     switch (refusal?.reason) {
@@ -270,6 +275,7 @@ export const CallFooter: FC<FooterProps> = ({
         onSelectBackgroundEffect={selectBackgroundEffect}
         backgroundEffectSettling={backgroundEffectSettling}
         onAddBackgroundImage={addBackgroundImage}
+        onRemoveBackgroundEffect={removeBackgroundEffect}
         backgroundImageRefusal={refusalMessage}
         backgroundEffectNotice={
           backgroundEffectNotice === "unavailable"

src/components/CallFooterViewModel.test.ts

@@ -51,6 +51,7 @@ vi.mock("@livekit/track-processors", () => ({
 
 const store = vi.hoisted(() => ({
   add: vi.fn<(file: Blob) => Promise<string>>(),
+  remove: vi.fn<(id: string) => Promise<void>>(),
 }));
 vi.mock("../livekit/backgroundImages", async (original) => {
   const { BehaviorSubject } = await import("rxjs");
@@ -59,6 +60,7 @@ vi.mock("../livekit/backgroundImages", async (original) => {
     addedBackgrounds: {
       added$: new BehaviorSubject<AddedBackground[] | undefined>([]),
       add: store.add,
+      remove: store.remove,
     },
   };
 });
@@ -324,21 +326,27 @@ describe("createCallFooterViewModel", () => {
       expect(lobbyOn("desktop").backgroundEffectNotice$.value).toBeUndefined();
     });
 
-    it("offers every effect in order", () => {
+    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" },
+        { id: "none", kind: "none", removable: false },
-        { id: "blur", kind: "blur" },
+        { id: "blur", kind: "blur", removable: false },
         ...shippedBackgrounds.map((background) => ({
           id: `image:${background.id}`,
           kind: "image",
           imageUrl: background.imagePath,
+          removable: false,
         })),
-        { id: "added:mine", kind: "image", imageUrl: "blob:mine" },
+        {
+          id: "added:mine",
+          kind: "image",
+          imageUrl: "blob:mine",
+          removable: true,
+        },
       ]);
       added$.next([]);
     });
@@ -412,6 +420,17 @@ describe("createCallFooterViewModel", () => {
       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("availability is the same before and during a call", () => {
       for (const supported of [true, false]) {
         sdkSupportMock.mockReturnValue(supported);

src/components/CallFooterViewModel.tsx

@@ -109,6 +109,7 @@ function buildDeviceBehaviors(
   | "backgroundEffectSettling$"
   | "addBackgroundImage$"
   | "backgroundImageRefusal$"
+  | "removeBackgroundEffect$"
 > {
   const options$ = (
     available$: Behavior<Map<string, MenuOptions["label"]>>,
@@ -210,6 +211,25 @@ function buildDeviceBehaviors(
       ),
     ),
     backgroundImageRefusal$: refusal$,
+    // Never the one in force: taking it away would leave nothing chosen.
+    removeBackgroundEffect$: 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,
+        ),
+      ),
+    ),
   };
 }
 
@@ -381,17 +401,19 @@ function backgroundEffectChoices(
   added: AddedBackground[],
 ): BackgroundEffectChoice[] {
   return [
-    { id: serializeEffect({ kind: "none" }), kind: "none" },
+    { id: serializeEffect({ kind: "none" }), kind: "none", removable: false },
-    { id: serializeEffect({ kind: "blur" }), kind: "blur" },
+    { 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

@@ -374,6 +374,126 @@ export const BackgroundImageRefused: Story = {
   },
 };
 
+/** A flat picture, for backgrounds of one's own. */
+function swatch(colour: string): string {
+  return `data:image/svg+xml,${encodeURIComponent(
+    `<svg xmlns="http://www.w3.org/2000/svg" width="16" height="9"><rect width="16" height="9" fill="${colour}"/></svg>`,
+  )}`;
+}
+
+/** One's own backgrounds are removable, never the one in force. */
+export const AddedBackgroundsCanBeRemoved: Story = {
+  args: {
+    ...VideoUnmute.args,
+    backgroundEffects: [
+      ...effects,
+      {
+        id: "added:one",
+        label: "Background 3",
+        kind: "image",
+        imageUrl: swatch("#c2410c"),
+        removable: true,
+      },
+      {
+        id: "added:two",
+        label: "Background 4",
+        kind: "image",
+        imageUrl: swatch("#1d4ed8"),
+        removable: true,
+      },
+    ],
+    selectedBackgroundEffect: "added:one",
+    onRemoveBackgroundEffect: fn(),
+  },
+  play: async ({ args, canvasElement }) => {
+    const canvas = within(canvasElement);
+    await userEvent.click(canvas.getByRole("button", { name: "Camera" }));
+    const body = within(document.body);
+
+    const inForce = await body.findByRole("menuitemradio", {
+      name: "Background 3",
+    });
+    await expect(inForce).not.toHaveAttribute("aria-keyshortcuts");
+
+    const other = body.getByRole("menuitemradio", { name: "Background 4" });
+    await expect(other).toHaveAttribute("aria-keyshortcuts", "Delete");
+    other.focus();
+    await userEvent.keyboard("{Delete}");
+    await expect(args.onRemoveBackgroundEffect).toHaveBeenCalledWith(
+      "added:two",
+    );
+
+    const wrapper = other.parentElement!;
+    await userEvent.hover(wrapper);
+    const cross = wrapper.querySelector<HTMLElement>(
+      "[aria-hidden]:last-child",
+    )!;
+    const probe = document.createElement("span");
+    probe.style.color = "var(--cpd-color-icon-critical-primary)";
+    cross.append(probe);
+    const critical = getComputedStyle(probe).color;
+    probe.remove();
+    await expect(getComputedStyle(cross).color).toBe(critical);
+    const tile = other.getBoundingClientRect();
+    const box = cross.getBoundingClientRect();
+    await expect(box.right).toBeGreaterThan(tile.right);
+    await expect(box.top).toBeLessThan(tile.top);
+
+    await userEvent.hover(cross);
+    await waitFor(async () =>
+      expect(
+        [...document.body.querySelectorAll("div")].some(
+          (d) => d.textContent === "Remove" && d.offsetParent !== null,
+        ),
+      ).toBe(true),
+    );
+  },
+};
+
+/** Removing by pointer while the selection really changes. */
+export const RemovingWithLiveSelection: Story = {
+  args: AddedBackgroundsCanBeRemoved.args,
+  render: function WithLiveSelection(args): JSX.Element {
+    const [selected, setSelected] = useState("none");
+    const [offered, setOffered] = useState(args.backgroundEffects ?? []);
+    return (
+      <MediaMuteAndSwitchButton
+        {...args}
+        backgroundEffects={offered}
+        selectedBackgroundEffect={selected}
+        onSelectBackgroundEffect={setSelected}
+        onRemoveBackgroundEffect={(id): void =>
+          setOffered((current) => current.filter((o) => o.id !== id))
+        }
+      />
+    );
+  },
+  play: async ({ canvasElement }) => {
+    const canvas = within(canvasElement);
+    await userEvent.click(canvas.getByRole("button", { name: "Camera" }));
+    const body = within(document.body);
+
+    const tile = await body.findByRole("menuitemradio", {
+      name: "Background 4",
+    });
+    await userEvent.hover(tile);
+    const cross = tile.parentElement!.querySelector<HTMLElement>(
+      "[aria-hidden]:last-child",
+    )!;
+    await expect(cross).toBeVisible();
+    await userEvent.click(cross);
+
+    await waitFor(async () =>
+      expect(
+        body.queryByRole("menuitemradio", { name: "Background 4" }),
+      ).toBeNull(),
+    );
+    await expect(
+      body.getByRole("menuitemradio", { name: "None" }),
+    ).toHaveAttribute("aria-checked", "true");
+  },
+};
+
 /** In a short call the effects scroll into view with the list. */
 export const BackgroundEffectsScrollWhenTheyDoNotFit: Story = {
   args: {

src/components/MediaMuteAndSwitchButton.tsx

@@ -83,6 +83,8 @@ 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, 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 };
   /**
@@ -120,6 +122,7 @@ export const MediaMuteAndSwitchButton: FC<MediaMuteAndSwitchButtonProps> = ({
   backgroundEffectNotice,
   backgroundEffectSettling,
   onAddBackgroundImage,
+  onRemoveBackgroundEffect,
   backgroundImageRefusal,
   onSelect,
 }) => {
@@ -492,6 +495,8 @@ export const MediaMuteAndSwitchButton: FC<MediaMuteAndSwitchButtonProps> = ({
                     }
               }
               addLabel={t("action.add_background_image")}
+              onRemove={onRemoveBackgroundEffect}
+              removeLabel={t("action.remove")}
             />
           )}
           {/* In the list, so the menu grows no taller for it. */}

src/livekit/backgroundImages.test.ts

@@ -81,6 +81,23 @@ describe("AddedBackgrounds", () => {
     expect(await storage.list()).toHaveLength(maxAddedBackgrounds);
   });
 
+  it("forgets a removed image, and lets its picture go", async () => {
+    const revoke = vi
+      .spyOn(URL, "revokeObjectURL")
+      .mockImplementation(() => {});
+    const storage = memoryStorage();
+    const store = new AddedBackgrounds(storage, asGiven);
+    await flushPromises();
+    const first = await store.add(new Blob(["a"]));
+    const second = await store.add(new Blob(["b"]));
+    const url = store.added$.value![0].url;
+
+    await store.remove(first);
+    expect(store.added$.value?.map((a) => a.id)).toEqual([second]);
+    expect((await storage.list()).map((k) => k.id)).toEqual([second]);
+    expect(revoke).toHaveBeenCalledWith(url);
+  });
+
   it("offers nothing where the browser keeps nothing", async () => {
     const store = new AddedBackgrounds(null);
     await flushPromises();
@@ -116,7 +133,7 @@ describe("prepareImage", () => {
 });
 
 describe("IndexedDBImageStorage", () => {
-  it("keeps images across sessions", async () => {
+  it("keeps images across sessions until they are deleted", async () => {
     const indexedDB = new IDBFactory();
     const image = new Blob(["x"], { type: "image/webp" });
     const first = new IndexedDBImageStorage(indexedDB);
@@ -131,6 +148,8 @@ describe("IndexedDBImageStorage", () => {
       ["a", 1],
       ["b", 2],
     ]);
+    await second.delete("a");
+    expect((await first.list()).map(({ id }) => id)).toEqual(["b"]);
   });
 });
 
@@ -144,5 +163,10 @@ function memoryStorage(kept: KeptImage[] = []): BackgroundImageStorage {
       kept.push(image);
       return Promise.resolve();
     },
+    delete: async (id): Promise<void> => {
+      const index = kept.findIndex((k) => k.id === id);
+      if (index !== -1) kept.splice(index, 1);
+      return Promise.resolve();
+    },
   };
 }

src/livekit/backgroundImages.ts

@@ -42,6 +42,7 @@ export interface KeptImage {
 export interface BackgroundImageStorage {
   list(): Promise<KeptImage[]>;
   put(image: KeptImage): Promise<void>;
+  delete(id: string): Promise<void>;
 }
 
 /** The backgrounds this device keeps, which never leave it. */
@@ -96,6 +97,14 @@ export class AddedBackgrounds {
     ]);
     return kept.id;
   }
+
+  public async remove(id: string): Promise<void> {
+    await this.storage?.delete(id);
+    const current = this.subject$.value ?? [];
+    const gone = current.find((a) => a.id === id);
+    if (gone) URL.revokeObjectURL(gone.url);
+    this.subject$.next(current.filter((a) => a.id !== id));
+  }
 }
 
 /**
@@ -190,6 +199,10 @@ export class IndexedDBImageStorage implements BackgroundImageStorage {
   public async put(image: KeptImage): Promise<void> {
     await this.run("readwrite", (s) => s.put(image));
   }
+
+  public async delete(id: string): Promise<void> {
+    await this.run("readwrite", (s) => s.delete(id));
+  }
 }
 
 function openStorage(): BackgroundImageStorage | null {