message: Event List Summary guard against missing event senders
diff: @@ -485,7 +485,7 @@ export default class EventListSummary extends React.Component<IProps> {
  if (e.target && TARGET_AS_DISPLAY_NAME_EVENTS.includes(type as EventType)) {
  latestUserAvatarMember.set(userId, e.target);
  - } else {
  + } else if (e.sender) {
  latestUserAvatarMember.set(userId, e.sender);
  }
  @@ -494,7 +494,7 @@ export default class EventListSummary extends React.Component<IProps> {
  displayName = e.getContent().display_name;
  } else if (e.target && TARGET_AS_DISPLAY_NAME_EVENTS.includes(type as EventType)) {
  displayName = e.target.name;
  - } else {
  + } else if (e.sender) {
  displayName = e.sender.name;
  }
  