bug#37700: 27.0.50; undo mouse-drag-and-drop-region ineffective

[Eli Zaretskii]

> Date: Fri, 11 Oct 2019 21:36:05 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 37700@debbugs.gnu.org
> 
> You are arguing that 'undo' should never be sensitive to the active
> region.  If that was so, we'd have gobs of bug reports, because this
> behavior is quite old, since 2007 AFAICT.

Actually, more like since 1998: it was introduced in Emacs 20.3.