bug#61667: 29.0.60; Failure to redisplay

[Dmitry Gutov]

On 25/02/2023 09:57, Eli Zaretskii wrote:
> > Date: Sat, 25 Feb 2023 01:34:32 +0200
> > Cc: Po Lu<luangruo@yahoo.com>,61667@debbugs.gnu.org,
> >   Eli Zaretskii<eliz@gnu.org>
> > From: Dmitry Gutov<dgutov@yandex.ru>
> >
> > Anyway, I couldn't reproduce the problem under it either. Emacs's
> > startup was noticeably slower there as well, though. Just like under
> > Window Maker. I wonder what could be the reason for both.
> Since this issue is all about timing, I'm not sure if the slower
> startup somehow makes the problem disappear or be masked, similarly to
> adding printfs (although the printfs effect is much better explained
> by some problem with damage tracking than by timing alone).

Damage tracking is indeed the better explanation, but I've also had the 
problem disappear when a certain background window was present. Even 
when entirely occluded.