bug#23468: Feature request: highlight Edebug breakpoints

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: pogonyshev@gmail.com,  23468@debbugs.gnu.org
> Date: Sun, 20 Oct 2019 13:12:43 +0200
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> >> I've now added highlights for the breakpoints in Emacs 27.
> >
> > Thanks, but why isn't this in NEWS and in the ELisp manual?
> 
> I didn't think it was NEWS-worthy (or documentation-worthy): It just
> a visual signifier that should have been there all along.

I think it should be documented because it presents a visual artifact
that users will need to understand.

And now that I see it in action, I think its visual appearance could
be improved.  What I see is the opening parenthesis of the form
highlighted in the 'highlight' face.  I think we should use a distinct
face, so that it doesn't "disappear" if the user has hl-line mode
enabled and so that users could customize it independently, and also I
think an indication similar to GUD (on the fringe etc.) would be
better: more prominent and much more self-explanatory.

Thanks.