bug#56695: A new and old font problem with Arabic

[Eli Zaretskii]

> Date: Sat, 13 Aug 2022 23:58:45 +0200 (CEST)
> From: "fr_ml@t-online.de" <fr_ml@t-online.de>
> Cc: "56695-done@debbugs.gnu.org" <56695-done@debbugs.gnu.org>
> 
> 
> Unfortunately I have another question.
> 
> Is it possible to force emacs to re-position the characters/glyphs?
> 
> It doesn't help to re-open the file.
> The command:
> (set-fontset-font "fontset-default" 'arabic "ANOTHER FONT") 
> helps only for one-time. After some typing re-using the command doesn't help.
> 
> This command:
> M-: (clear-composition-cache) RET
> seems to change something but it doesn't help.
> 
> Somehow Emacs seems to remember the false positioning of the characters.
> If I a start a new Emacs the problem disappears (for some time, as I said).
> 
> So how can I let Emacs "forget" the false positioning and make a new one?

If clear-composition-cache doesn't help, I don't know any way short of
restarting Emacs.  Sorry.