bug#50660: 28.0.50; Text artifacting when the cursor moves over text under mouse face that originally displayed a box

[Eli Zaretskii]

> From: Po Lu <luangruo@yahoo.com>
> Cc: 50660@debbugs.gnu.org
> Date: Sun, 17 Oct 2021 08:32:46 +0800
> 
> >   1) After producing the mouse face, you should call
> >      prepare_face_for_display.
> >
> >   2) The code you add in set_glyph_string_background_width is almost
> >      identical to what we already have inside the loop in
> >      get_cursor_offset_for_mouse_face, and I wonder whether we could
> >      have a function to be called from these two places.
> >
> > Other than that, I think this is fine, thanks.
> 
> Does this resolve your concerns?  Thanks.

Thanks, installed with some minor adaptations (the main of which was
to find a shorter name for the new function).