bug#52881: setting tab-line-separator to any value breaks clicking tabs with mouse

[Eli Zaretskii]

> From: Juri Linkov <juri@linkov.net>
> Cc: ben.sferrazza@aeonsemi.com,  52881@debbugs.gnu.org
> Date: Thu, 30 Dec 2021 18:08:12 +0200
> 
> >> Eli, is it ok to push this patch to the release branch
> >> to support longer separators:
> >
> > Yes, but can you make it a bit cleaner?  Like having a single function
> > to do that, and also not calling next-single-property-change twice an
> > a row?
> 
> I could optimize this, but I wonder why there is no simple function
> to find a text property and its first value in the string?

I don't know.  We could add something like that, but that would not be
for the release branch.