bug#18793: 24.4; zero width rectangular selection displaces text

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: carlosjosepita@gmail.com,  monnier@iro.umontreal.ca,  
> 18793@debbugs.gnu.org
> Date: Sat, 07 May 2022 12:18:44 +0200
> 
> Lars Ingebrigtsen <larsi@gnus.org> writes:
> 
> > Point on the indicator:
> 
> D'oh!  Sorry; that's not special handling at all -- it's just the normal
> point-on-character handling.

More accurately, we display the indicator instead of a stretch glyph
that stands for the newline or the empty space after EOL.