bug#11732: Follow-up to bug#11732

[Eli Zaretskii]

> From: Noam Postavsky <npostavs@gmail.com>
> Date: Thu, 28 Jun 2018 15:17:34 -0400
> Cc: Masayuki Hatta <mhatta@gmail.com>, 11732@debbugs.gnu.org
> 
> I tried also after applying the "activate a window by hovering over it
> with a mouse", and it made no difference (to Emacs, that is).

Thanks for trying.  Nevertheless, the effect is 100% reproducible on 2
different systems where I regularly work, so I'd like to try to get to
the bottom of that.