Bug 424586

Summary:	Firefox flickers terribly
Product:	[Plasma] kwin	Reporter:	Nate Graham <nate>
Component:	wayland-generic	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	normal	CC:	aleixpol, bugseforuns, butirsky, germano.massullo, kde, rainer
Priority:	NOR
Version:	git master
Target Milestone:	---
Platform:	Other
OS:	Linux
URL:	https://bugzilla.mozilla.org/show_bug.cgi?id=1685263
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	system env

Description Nate Graham 2020-07-23 21:19:35 UTC

Created attachment 130350 [details]
system env

All KDE software built from git master as of five minutes ago.

Firefox flickers horribly on Wayland for me. The experience makes Firefox practically unusable. A video showing what it looks like can be found here: https://www.dropbox.com/s/4xbknleyvscmycn/video.zip?dl=0 (it's too large to upload)

This happens with the XWayland version, or with GDK_BACKEND="wayland" set in the environment, or without that envar set at all, or when run from weston-terminal inside KWin.

Comment 1 Nate Graham 2020-07-23 21:20:36 UTC

Using Basic compositing mode in Firefox.

Comment 2 Aleix Pol 2020-07-24 00:35:02 UTC

I don't see it running MOZ_ENABLE_WAYLAND=1.

Comment 3 Nate Graham 2020-07-24 03:01:03 UTC

There is no improvement whatsoever with MOZ_ENABLE_WAYLAND=1 set. :(

Comment 4 Patrick Silva 2020-07-24 12:25:47 UTC

I can confirm this issue with Firefox running natively on Wayland and with web renderer disabled. Enabling web renderer fixes these glitches on my system.

Comment 5 Andrey 2020-07-24 14:44:50 UTC

So we seem have at least 2 FF settings witch influence - compositing mode and web renderer.
With default settings the bug should arise.

Comment 6 Nate Graham 2020-07-24 21:23:36 UTC

Confirmed, the problem is completely resolved when manually enabling WebRender by setting gfx.webrender.all to true in Firefox's about:config window.

Comment 7 David Edmundson 2020-08-05 13:28:27 UTC

And naturally I immediately set mine to false to reproduce and debug it :)

The situation is quite weird. We are getting alternate buffers from firefox that are of different sizes.

Based purely on my logs, kwin is entirely in the right and firefox is sending us garbage data.

Comment 8 Nate Graham 2020-08-05 14:02:16 UTC

You're the hero we need but don't deserve. :)

Comment 9 Andrey 2020-08-10 19:33:50 UTC

So is it looks like FF problem? If so, should we report it there?

Comment 10 Vlad Zahorodnii 2020-08-17 19:52:21 UTC

Yes and no. If Firefox sends garbage buffers, the window contents should only bounce. No visual artifacts like the ones in the first comment should be visible.