> From: Philipp Stephani <p.stephani2@gmail.com>
> Date: Fri, 09 Sep 2016 15:59:02 +0000
> Cc: 24372@debbugs.gnu.org
>
> Eli Zaretskii <eliz@gnu.org> schrieb am Di., 6. Sep. 2016 um 18:03 Uhr:
>
>  > From: Philipp Stephani <p.stephani2@gmail.com>
>  > Date: Mon, 05 Sep 2016 21:16:40 +0200
>  >
>  > emacs -Q -eval '(setq blink-cursor-delay 0.0)'
>  >
>  > Move point around in the scratch buffer (e.g. press C-b a couple of
>  > times): the cursor stays visible, as it should be. Then put the mouse
>  > focus on a different GTK window (not Emacs window), put the mouse focus
>  > back on Emacs, and move point again: the cursor is hidden, making it
>  > impossible to see until you stop moving.
>
>  Does it happen even if you wait with cursor motion until after the
>  cursor blinks one time, i.e. if you start moving point with the cursor
>  already visible after Emacs gets focus?
>
> Yes. No matter what state the cursor is in and how often it has already blinked, it becomes invisible when
> moving.

So what is the importance of moving focus out of the Emacs frame and
then back into it?  Is the problem reproducible without that?  Or are
you saying that focus-out followed by focus-in event somehow changes
the behavior wrt displaying the cursor?