bug#26742: Display bug with composed strings

[Eli Zaretskii]

> Date: Tue, 02 May 2017 20:57:45 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 26742@debbugs.gnu.org
> 
> > Cc: 26742@debbugs.gnu.org
> > From: Clément Pit--Claudel <clement.pitclaudel@live.com>
> > Date: Tue, 2 May 2017 13:22:19 -0400
> > 
> > For ℝ, "emacs -Q" uses "Latin Modern Math" and "emacs" with customizations 
> > uses "XITS Math". 
> > For ≤, both use Ubuntu Mono.  I changed the default font and noticed 
> > slightly different glitches, including with a variable-pitch font multiple 
> > "!" disappearing.
> 
> Could you try fonts mentioned by Andreas?

Also, what happens if you replace 8804 in your test file with 10877?