@Override
    public void contentRemoved(@NotNull ContentManagerEvent event) {
      final Content eventContent = event.getContent();
      if (!eventContent.equals(myContent)) {
        return;
      }
      myMessageView.getContentManager().removeContentManagerListener(this);
      NewErrorTreeViewPanel errorTreeView = eventContent.getUserData(KEY);
      if (errorTreeView != null) {
        Disposer.dispose(errorTreeView);
      }
      eventContent.putUserData(KEY, null);
    }
@Override
    public void contentRemoved(@NotNull ContentManagerEvent event)