Comment 2 for bug 1876609

If I run
   gnome-panel --replace &
and then add gnubiff to panel (when mail is pending) then I get

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(gnome-panel:1856): Gdk-ERROR **: 17:36:46.221:
The program 'gnome-panel' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadImplementation (server does not implement operation)'.
  (Details: serial 3682 error_code 17 request_code 20 (core protocol) minor_code 0)
  (Note to programmers: normally, X errors are reported asynchronously;
   that is, you will receive the error a while after causing it.
   To debug your program, run it with the GDK_SYNCHRONIZE environment
   variable to change this behavior. You can then get a meaningful
   backtrace from your debugger if you break on the gdk_x_error() function.)
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If I run
    GDK_SYNCHRONIZE=1 gnome-panel --replace &
then I get

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[xcb] Unknown sequence number while processing queue
[xcb] Most likely this is a multi-threaded client and XInitThreads has not been called
[xcb] Aborting, sorry about that.
gnome-panel: ../../src/xcb_io.c:259: poll_for_event: Assertion `!xcb_xlib_threads_sequence_lost' failed.
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