Subject: Re: bug#67267: 29.1.90; Buffer's modified flag remains after undoing

From: Eli Zaretskii <[email-masked]>
Date: Sun, 19 Nov 2023 08:12:21 +0200

unarchive 66244
forcemerge 67267 66244
thanks

> From: Óscar Fuentes <[email-masked]>
> Date: Sun, 19 Nov 2023 03:10:21 +0100
> 
> 
> $ emacs -Q xdisp.c
> 
> Highlight a region with C-SPC <cursor down>
> 
> M-x comment-region
> 
> M-x undo
> 
> The change is undone, but the buffer is still marked as modified.

This is a known bug, which is already fixed on the master branch (and
will remain unfixed on emacs-29).