bug#58282: Distinguishing glasses-mode display

[Christopher Dimech]

> Sent: Tuesday, October 04, 2022 at 7:18 PM
> From: "Eli Zaretskii" <eliz@gnu.org>
> To: "uzibalqa" <uzibalqa@proton.me>
> Cc: 58282@debbugs.gnu.org
> Subject: bug#58282: Distinguishing glasses-mode display
>
> > Date: Tue, 04 Oct 2022 03:36:34 +0000
> > From:  uzibalqa via "Bug reports for GNU Emacs,
> >  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> >
> >
> > I am using "glasses-mode", but  It is difficult to distinguish which words 
> > get changed. For instance, if one has a mixture of CamelCase, Under_scores 
> > one would not know which is modified and which is original. Particularly 
> > problematic when one is modifying the code.
> >
> > Could "glasses-mode" be made in such way as to indicate that "glasses-mode" 
> > changed its display, by default.
>
> I think we have this already: customize glasses-face to some distinct
> face, like 'bold'.  Then the capital letters of identifiers where
> glasses.el inserted underscores will be shown in bold, and you can
> visually distinguish them from the original underscores.

Because I use bold font the default does not work for me.  I want to
make the changes in my init file.  How can I change the foreground
and background colour of the glasses matches?  Is it possible for users
to use a UTF8 Code as separator, and if so, how can this be done?