message: Support M_INCOMPATIBLE_ROOM_VERSION
  For
diff: @@ -223,7 +223,13 @@ class RoomViewStore extends Store {
  action: 'join_room_error',
  err: err,
  });
  - const msg = err.message ? err.message : JSON.stringify(err);
  + let msg = err.message ? err.message : JSON.stringify(err);
  + if (err.errcode === 'M_INCOMPATIBLE_ROOM_VERSION') {
  + msg = <div>
  + {_t("Sorry, your homeserver is too old to participate in this room.")}<br />
  + {_t("Please contact your homeserver administrator.")}
  + </div>;
  + }
  const ErrorDialog = sdk.getComponent("dialogs.ErrorDialog");
  Modal.createTrackedDialog('Failed to join room', '', ErrorDialog, {
  title: _t("Failed to join room"),
  