bug#67794: 30.0.50; mouse-face is not respected on SVG images

[Eli Zaretskii]

> From: Manuel Giraud <manuel@ledu-giraud.fr>
> Cc: alan@idiocy.org,  67794@debbugs.gnu.org
> Date: Wed, 13 Dec 2023 17:50:08 +0100
> 
> BTW, do you know why mouse-highlight is this way?  Is it because it
> was an afterthought of the display engine or is it because of
> performance issues or…?

How would you design it instead?

I'm not saying that what we have is the only possible design, but I'm
curious what alternative design ideas could be used.

Btw, AFAIU the person who at the time decided how this will work is
here: it's Gerd (CC'ed).  Maybe he can share his memories about why he
ended up with this design.