bug#25906: 25.1; strange behavior of overlapped mouse-face

[Glenn Morris]

Eli Zaretskii wrote:

> That would be the wrong thing to do, IMO.  The mouse-face is not just
> any face, it is designed for showing an "active region" of text, where
> mouse gestures produce certain effects.  Such region is also customary
> has a help-echo defined to show the appropriate tooltip.  It therefore
> makes no sense to merge mouse-face definitions that come from several
> different sources, because there could be only one action that will
> happen upon those mouse gestures, and mixing several help-echo texts
> makes no sense either.  So Emacs shows only one mouse-face of several
> possible ones.

Makes sense to me, thanks.