bug#39340: 26.3; "Noto Emoji" font not displayed

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: Robert Pluim <rpluim@gmail.com>,  39340@debbugs.gnu.org,  ynyaaa@gmail.com
> Date: Sun, 20 Sep 2020 12:08:59 +0200
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> >> It looks like ScriptShape is failing.
> >
> > OK.
> >
> >>     Eli> This could be a symptom of Microsoft deprecating Uniscribe.
> >> 
> >> Then we should deprecate it as well, no?
> >
> > We did -- by switching to HarfBuzz as our primary shaping engine.
> 
> Skimming this thread, it's unclear whether there's anything to fix
> here...  perhaps a note about this situation in etc/PROBLEMS?

I'm not really sure what would we write in PROBLEMS.  That some
unnamed characters don't display correctly when HarfBuzz is not
installed, and that if this happens, we suggest to install HarfBuzz
and/or build Emacs with HarfBuzz support?  If such a vague entry is
deemed useful, I can write it.  But note that build with HarfBuzz is
nowadays the default, so the problem could happen only in rare corner
use cases.