diff --git a/src/state/CallViewModel.test.ts b/src/state/CallViewModel.test.ts
index 4adfb291..c5c47272 100644
--- a/src/state/CallViewModel.test.ts
+++ b/src/state/CallViewModel.test.ts
@@ -6,7 +6,7 @@ Please see LICENSE in the repository root for full details.
 */
 
 import { test, vi, onTestFinished } from "vitest";
-import { map, Observable } from "rxjs";
+import { map, Observable, of } from "rxjs";
 import { MatrixClient } from "matrix-js-sdk/src/matrix";
 import {
   ConnectionState,
@@ -25,10 +25,11 @@ import {
   mockLivekitRoom,
   mockLocalParticipant,
   mockMatrixRoom,
-  mockMember,
+  mockRoomMember,
   mockRemoteParticipant,
   OurRunHelpers,
   withTestScheduler,
+  mockMembership,
 } from "../utils/test";
 import {
   ECAddonConnectionState,
@@ -49,9 +50,9 @@ const bobId = "@bob:example.org";
 const bobDev = "BBBB";
 const bobRTCId = bobId + ":" + bobDev;
 
-const alice = mockMember({ userId: aliceId });
-const bob = mockMember({ userId: bobId });
-const carol = mockMember({ userId: carolId });
+const alice = mockRoomMember({ userId: aliceId });
+const bob = mockRoomMember({ userId: bobId });
+const carol = mockRoomMember({ userId: carolId });
 
 const localParticipant = mockLocalParticipant({ identity: "" });
 const aliceParticipant = mockRemoteParticipant({ identity: aliceRTCId });
@@ -71,9 +72,10 @@ const members = new Map([
   [carol.userId, carol],
 ]);
 
-const rtcMemberAlice = { sender: aliceId, deviceId: aliceDev };
-const rtcMemberBob = { sender: bobId, deviceId: bobDev };
-const rtcMemberCarol = { sender: carolId, deviceId: carolDev };
+const rtcMemberAlice = mockMembership(aliceId, aliceDev);
+const rtcMemberBob = mockMembership(bobId, bobDev);
+const rtcMemberCarol = mockMembership(carolId, carolDev);
+
 export interface GridLayoutSummary {
   type: "grid";
   spotlight?: string[];
@@ -262,6 +264,7 @@ test("screen sharing activates spotlight layout", () => {
         c: [aliceSharingScreen, bobSharingScreen],
         d: [aliceParticipant, bobSharingScreen],
       }),
+      of([rtcMemberAlice, rtcMemberAlice]),
       hot("a", { a: ConnectionState.Connected }),
       (vm) => {
         schedule(modeMarbles, {
diff --git a/src/utils/test.ts b/src/utils/test.ts
index d2014afb..1caef0ab 100644
--- a/src/utils/test.ts
+++ b/src/utils/test.ts
@@ -7,7 +7,16 @@ Please see LICENSE in the repository root for full details.
 import { map, of } from "rxjs";
 import { RunHelpers, TestScheduler } from "rxjs/testing";
 import { expect, vi } from "vitest";
-import { RoomMember, Room as MatrixRoom } from "matrix-js-sdk/src/matrix";
+import {
+  RoomMember,
+  Room as MatrixRoom,
+  MatrixEvent,
+} from "matrix-js-sdk/src/matrix";
+import {
+  CallMembership,
+  Focus,
+  SessionMembershipData,
+} from "matrix-js-sdk/src/matrixrtc";
 import {
   LocalParticipant,
   LocalTrackPublication,
@@ -88,10 +97,32 @@ function mockEmitter<T>(): EmitterMock<T> {
   };
 }
 
+export function mockMembership(
+  userId: string,
+  deviceId: string,
+  callId = "",
+  fociPreferred: Focus[] = [],
+  focusActive: Focus = { type: "oldest_membership" },
+  membership: Partial<SessionMembershipData> = {},
+): CallMembership {
+  const data: SessionMembershipData = {
+    application: "m.call",
+    call_id: callId,
+    device_id: deviceId,
+    foci_preferred: fociPreferred,
+    focus_active: focusActive,
+    ...membership,
+  };
+  const event = new MatrixEvent({
+    sender: userId,
+  });
+  return new CallMembership(event, data);
+}
+
 // Maybe it'd be good to move this to matrix-js-sdk? Our testing needs are
 // rather simple, but if one util to mock a member is good enough for us, maybe
 // it's useful for matrix-js-sdk consumers in general.
-export function mockMember(member: Partial<RoomMember>): RoomMember {
+export function mockRoomMember(member: Partial<RoomMember>): RoomMember {
   return { ...mockEmitter(), ...member } as RoomMember;
 }
 
@@ -121,7 +152,7 @@ export async function withLocalMedia(
 ): Promise<void> {
   const vm = new LocalUserMediaViewModel(
     "local",
-    mockMember(member),
+    mockRoomMember(member),
     of(mockLocalParticipant({})),
     {
       kind: E2eeType.PER_PARTICIPANT,
@@ -154,7 +185,7 @@ export async function withRemoteMedia(
 ): Promise<void> {
   const vm = new RemoteUserMediaViewModel(
     "remote",
-    mockMember(member),
+    mockRoomMember(member),
     of(mockRemoteParticipant(participant)),
     {
       kind: E2eeType.PER_PARTICIPANT,