bug#39799: 28.0.50; Most emoji sequences don’t render correctly

[Eli Zaretskii]

> From: Robert Pluim <rpluim@gmail.com>
> Cc: rgm@gnu.org,  39799@debbugs.gnu.org
> Date: Fri, 24 Sep 2021 13:41:07 +0200
> 
> Yes. Iʼve now pushed exactly that to master. There are two types of
> sequences that donʼt work:
> 
> 1. Where the base character has Emoji_Presentation = No, hence we
> donʼt consider it for composition. These are all in the U+2xxx range,
> since we explicitly override this for those in the U+1xxxx range. They
> do have Emoji_Modifier_Base = Yes, but we donʼt currently do anything
> with that info. I guess if we managed to store it in a codepoint
> property somewhere, we could teach set-fontset-font or the composition
> code about it, but itʼs far too close to emacs-28 for that.

The idea was to make this work with the patch to font_range on which
you were working?

> (this does not include the change for choosing emoji presentation for
> codepoints followed by VS-16; that still needs some work).

That one is not just for VS-16, right?

Thanks.