message: Oops, we still used this cache for new incoming virtual rooms
diff: @@ -24,6 +24,8 @@ import { Room } from 'matrix-js-sdk/src/models/room';
  // is sip virtual: there could be others in the future.
  export default class VoipUserMapper {
  + private virtualRoomIdCache = new Set<string>();
  +
  public static sharedInstance(): VoipUserMapper {
  if (window.mxVoipUserMapper === undefined) window.mxVoipUserMapper = new VoipUserMapper();
  return window.mxVoipUserMapper;
  @@ -61,6 +63,8 @@ export default class VoipUserMapper {
  public isVirtualRoom(room: Room):boolean {
  if (this.nativeRoomForVirtualRoom(room.roomId)) return true;
  + if (this.virtualRoomIdCache.has(room.roomId)) return true;
  +
  // also look in the create event for the claimed native room ID, which is the only
  // way we can recognise a virtual room we've created when it first arrives down
  // our stream. We don't trust this in general though, as it could be faked by an
  