Re: [External] : Re: Strange whitespaces.

[Eli Zaretskii]

> From: Drew Adams <drew.adams@oracle.com>
> Date: Thu, 30 Sep 2021 15:20:30 +0000
> 
> > Why are both displayed as red underscores in Emacs?
> 
> I don't think the EN SPACE is displayed that way.
> Not with `emacs -Q' (no init file), at least.  But
> I don't have an Emacs 28 prerelease build - maybe
> they changed Emacs 28 to highlight that as well.

They did.  We now highlight any non-ASCII character whose Unicode
general category is "Space Separator" (or Zs for short).  That
includes EN SPACE.

> Note that `nobreak-char-display' highlights all
> no-break (aka "hard") characters, not just the
> no-break space.  IOW, it highlights hard hyphens
> (code point 8209) as well as hard spaces.

It highlights much more, see above.