My patch is all in xdisp.c so I don't follow.

On Thu, Feb 27, 2025 at 14:07 Juri Linkov <juri@linkov.net> wrote:

> > I assumed you knew how to use tab-bar :) I rarely use emojis but this
> one I
> > couldn't help myself.
> >
> > It also works with mouse-face on any spans of glyphs embedded in the name
> > string.
>
> But this doesn't look normal, don't you think so?
> tab-bar-mode enabled, then later disabled,
> code evaluated, enabled again, and no effect.
> Something is wrong here?  There are no other settings
> that behave that way.
>
> >     > (defun my/tab-bar-tab-name-format-function (tab i)
> >     >   (propertize
> >     >    (tab-bar-tab-name-format-default tab i)
> >     >    'mouse-face '(:inverse-video t))) ; or a named face
> >     > (setopt tab-bar-tab-name-format-function
> >     > #'my/tab-bar-tab-name-format-function)
> >     >
> >     > And move the mouse over the tab. It should invert. It does for me.
> >
> >     Thanks, now it works.  The requirement is that the tab-bar-mode
> >     should be disabled before evaluating the above code.  Otherwise,
> >     with already enabled tab-bar-mode it has no effect.
>