bug#61667: 29.0.60; Failure to redisplay

[Eli Zaretskii]

> Date: Sun, 16 Apr 2023 20:46:39 +0300
> From: "Dmitry Gutov" <dgutov@yandex.ru>
> 
>  When you say "gets updated noticeably faster", what exactly do you
>  mean? by how much time does the redraw of the windows lag after the
>  title bar update?
> 
> Can be on the order of seconds or indefinitely, just like described before.

That's strange.  Po Lu, what could prevent the results of rdisplay
from appearing on the glass in this case?  AFAIR, we simply call
XFlush when the update of the frame is done; we don't wait for any X
event to trigger redrawing on the glass.

Dmitry, does this happen with Emacs 28?