bug#61667: 29.0.60; Failure to redisplay

[Dmitry Gutov]

On 02/03/2023 09:11, Eli Zaretskii wrote:
> > From: Po Lu<luangruo@yahoo.com>
> > Cc:61667@debbugs.gnu.org,  Gregory Heytings<gregory@heytings.org>,  Eli
> >   Zaretskii<eliz@gnu.org>
> > Date: Thu, 02 Mar 2023 12:11:38 +0800
> >
> > Yes.  It sure sounds like a bug in the GNOME compositor now.
> > Have you tried disabling GNOME Shell extensions one by one?  Maybe one
> > of them is responsible for this.
> Whether or not we find some workarounds, I think we should add an
> entry to PROBLEMS about this.

Speaking of disabling double buffering as a workaround: I went back to 
my old bug reports related to flickering, which double-buffering aimed 
to fix.

I recompiled the GTK3 build without xdbe -- and still couldn't reproduce 
neither bug#12363 (which was admittedly filed on a Windows system), nor 
bug#16621. Even with the same font (Fira Code).

Not sure what changed -- maybe better screen resolution, or a faster 
machine. And the DE, libraries' versions, etc.

But there is a persistent glitch: when the window configuration changes, 
1 or 2 vertical bars often flash:

https://a.uguu.se/iYTlOftH.mp4 (with emacs -Q)

https://a.uguu.se/YdDWpMid.mp4 (with my config but with tool-bar and 
scroll-bar modes enabled)

scroll-bar-mode on seems to be required to reproduce this.