message: Opt out from check for pre-join UISI for threads
diff: @@ -1331,8 +1331,12 @@ class TimelinePanel extends React.Component<IProps, IState> {
  private checkForPreJoinUISI(events: MatrixEvent[]): number {
  const room = this.props.timelineSet.room;
  - if (events.length === 0 || !room ||
  - !MatrixClientPeg.get().isRoomEncrypted(room.roomId)) {
  + const isThreadTimeline = [TimelineRenderingType.Thread, TimelineRenderingType.ThreadsList]
  + .includes(this.context.timelineRenderingType);
  + if (events.length === 0
  + || !room
  + || !MatrixClientPeg.get().isRoomEncrypted(room.roomId)
  + || isThreadTimeline) {
  return 0;
  }
  