Your bug report

#36680: 27.0.50; undo-tree visualizer flickering with display-buffer-reuse-frames -> t

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 36680@debbugs.gnu.org.

-- 
36680: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=36680
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