bug#63407: 29.0.90; <mouse-2> on misspelled word hangs X11

[Eli Zaretskii <eliz@gnu.org>]

merge 63406 63408 63404 63407
thanks

> From: Doug Maxey <emacs-bugs@maxeygroup.tech>
> Date: Tue, 09 May 2023 16:15:09 -0500
> 
> 
> The setup:
> - rocky-9 x86_64.
> - The graphics session is running in "classic", i.e. Xorg, not wayland.
> - multi-monitors joined to single display.
> - emacs-lucid from locally built rpm (non-rpm local build behaves same).
> - buffer major-mode does not seem to matter.
> - <mouse-2> on a misspelled word.
> 
> The result is other than having control of the sprite (the mouse can
> move the sprite around normally. and I can switch tty with Ctrl-Alt-N)
> there is NO other input accepted.  Cannot select any other window than
> the last (emacs frame in this case), and there is no keyboard or mouse
> button input.  There are no visible change on the screen, no dialog box
> pops up.
> 
> The net effect is that the screen is frozen, save for the moving sprite.

Please reproduce this, preferably in "emacs -Q", then attach GDB to
the "frozen" Emacs process, and type at the GDB prompt:

   thread apply all bt

and post here everything that GDB prints as result.

Thanks.