Re: Unicode confusables and reordering characters considered harmful, a simple solution

[Gregory Heytings]

> > > > Anyway, if one wants to be able to highlight certain characters on 
> > > > display, one could also use highlight-regexp, I think.
> > >
> > > Or markchars.el with markchars-what customized to 
> > > markchars-confusables.
> >
> > Neither would work AFAICS, because these characters are glyphless. 
> > Highlighting a glyphless character will not make it more visible.
>
> ??? Of course, it will make it more visible: if the face has a distinct 
> background.  The "thin space" display looks like whitespace, and 
> whitespace can have background color to make it stand out.

I tried various of the predefined colors with highlight-regexp, of course 
those with a distinct background, and none make any of those characters 
more visible.  Not even with a single pixel wide bar.