bug#58406: 29.0.50; Bars refactoring?

[Po Lu]

Manuel Giraud <manuel@ledu-giraud.fr> writes:

> mouse over highlight: like the relief on tool bar button or, even
> better, with highlight face like on the modeline.

I'm afraid I don't see the utility of that in a menu bar, since it
doesn't consist of "buttons" in the sense that the tool bar or tab bar
do, and no program does that anymore.

> I understand that it is too close to Emacs 29.  Do you think the menu
> bar could be made to mimic some feature of the tool bar (like tab bar
> did)?  Or do you think it would add to the cargo cult?

I'd rather not touch any of the *bar code before Emacs 29 is cut.  Most
people do not use the bars, leading to many latent bugs.  Examples:
mouse face not being cleared when tooltips are enabled and the mouse
moves outside the frame, last_tool_bar_item not being cleared in the
same case, and last_tab_bar_item not being cleared, leading to mouse
highlight not working after the mouse is released outside a frame.

These bugs are particularly nasty because they only happen in rare
situations, but can completely ruin the visual appearance of a frame
when they do.