bug#27544: 25.1; Visualization of Unicode bidirectional marks

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: Itai Berli <itai.berli@gmail.com>,  27544@debbugs.gnu.org
> Date: Wed, 01 Dec 2021 16:53:41 +0100
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> >> What would be the best way to implement such a mode?  Change
> >> `glyphless-char-display' buffer-locally?
> >
> > Yes, I think so.
> 
> OK; I've now added this under the name `glyphless-display-mode', and it
> seems to work fine in my test case (which is TUTORIAL.he).

Thanks.  But wouldn't glyphless-hex-display-mode be a better name?
glyphless-display-mode doesn't really say what it does to glyphless
characters.