Re: Suggest installing more fonts?

[Eli Zaretskii]

> Date: Fri, 16 Oct 2020 14:38:04 +0000
> From: Gregory Heytings <ghe@sdf.org>
> cc: larsi@gnus.org, emacs-devel@gnu.org
> 
> Another thought on this: to avoid "looking unprofessional", a help-echo 
> property could be added on these characters, saying something like 
> "Warning: no font installed for this character".  So the user would see an 
> ugly (but often recognizable) character, and at the same time would be 
> warned that they need to do something to see it better.

Yes, Lars suggested that as well.  But we have to be careful: too many
such properties or overlays will slow down redisplay.  Also, we'd need
to see how to do this technically, since characters that have no fonts
are discovered during redisplay.  Perhaps some jit-lock registered
function could detect them after redisplay, and put the properties on
some of them (which ones?).