bug#44236: [PATCH] xdisp: Apply nobreak-char-display also to NARROW NO-BREAK SPACE U+202F

[Juri Linkov]

>> Seeing hundreds of red underlines in Dired buffers is a horrible experience.
>
> You can turn the feature off locally in your Dired buffers, no?
>
> I mean, you've created this situation by customizing the Dired
> display, so customizing it a bit more should not be a grave problem,
> IMO.

Indeed, this should not be hard to do if a more general solution
can't be found.

> Text properties are handled by the display code on a level above
> get_next_display_element.
>
> But that's not what I meant.  I meant that if we want to base this on
> text properties, we should do this via hi-lock or similar, not in the
> display engine which treats all characters the same.

Or markchars.el, or uni-confusables.el.  Like these packages maybe better
to create another package e.g. nobreak.el, based on font-lock-mode?

> Alternatively, if this new feature is so annoying, and people are
> unwilling to customize their Emacs to get the old behavior back, maybe
> we should make nobreak-char-display more than just a simple boolean,
> so that people could control which characters are and aren't
> emphasized?

This would complicate the core functions.