bug#32950: 27.0.50; Strange display bug in *Help* buffer

[Eli Zaretskii]

> From: Stefan Kangas <stefan@marxist.se>
> Date: Sat, 6 Nov 2021 04:09:01 -0700
> Cc: 32950@debbugs.gnu.org, fgunbin@fastmail.fm
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > And, as I suspected, we now show no separator at all on those text
> > terminals which don't support the underline attribute.  This is a
> > regression, I think.
> 
> Can we detect those terminals that doesn't support underline and fall
> back to the old method for them?

Yes, of course.  See display-supports-face-attributes-p.