Bug 453465

Summary:	Some firefox windows disappear on a session restore on wayland
Product:	[Plasma] kwin	Reporter:	Gauthier <g.guerin>
Component:	wayland-generic	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED DOWNSTREAM
Severity:	normal	CC:	gus, kde, omerusta
Priority:	NOR
Version First Reported In:	5.24.5
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Gauthier 2022-05-06 12:45:16 UTC

SUMMARY
If rebooting or logout / login with several firefox windows opened on several screens and desktops, some firefox windows disappear on a session restore on wayland, whereas it works fine on X11 (in fact the windows have gone missing on wayland even reload fine when re-login back into X11).
I only use several windows for firefox, so this is the only app I could see the bug, but it might not be limited to it and it is possibly a wider problem.

STEPS TO REPRODUCE
1. Open several firefox windows on several screens and desktops on X11
2. Logout
3. Login on Wayland
4. Logout again
5. Login again
(maybe need to repeat 4. and 5 several times to see the bug)

OBSERVED RESULT
On the first login on Wayland, everything is restored properly, all the firefox windows are restored. But then on subsequent logins, some of them are missing. They are not anywhere on any screens or desktops (out of 7 firefox windows, only 2-3 are restored). When login back into X11, everything restores fine. This makes me think wayland is just not displaying the windows but they musty be somewhat still opened/running for them to restore when login back into X11.

EXPECTED RESULT
Everything should restore properly on wayland every time, as it does on X11.

Operating System: KDE neon 5.24
KDE Plasma Version: 5.24.5
KDE Frameworks Version: 5.93.0
Qt Version: 5.15.3
Kernel Version: 5.13.0-40-generic (64-bit)
Graphics Platform: X11
Processors: 8 × Intel® Core™ i5-8350U CPU @ 1.70GHz
Memory: 15.4 GiB of RAM
Graphics Processor: Mesa Intel® UHD Graphics 620

Comment 1 Ömer Fadıl USTA 2022-05-06 20:59:55 UTC

is this bug exist even if you run firefox on wayland support ? ( i mean normally firefox full wayland support only enabled when you run firefox with MOZ_ENABLE_WAYLAND=1  system variable . 

Add this lines at the end of your .bashrc file  and after a relogin/reboot could you check if that bug exist or not.

if [ "$XDG_SESSION_TYPE" == "wayland" ]; then
    export MOZ_ENABLE_WAYLAND=1
fi

Comment 2 Gauthier 2022-05-29 12:04:47 UTC

(In reply to Ömer Fadıl USTA from comment #1)
> is this bug exist even if you run firefox on wayland support ? ( i mean
> normally firefox full wayland support only enabled when you run firefox with
> MOZ_ENABLE_WAYLAND=1  system variable . 
> 
> Add this lines at the end of your .bashrc file  and after a relogin/reboot
> could you check if that bug exist or not.
> 
> if [ "$XDG_SESSION_TYPE" == "wayland" ]; then
>     export MOZ_ENABLE_WAYLAND=1
> fi

Hi, sorry it took me a while to try this.

Sadly it did not work, some windows were still missing on restore in Wayland. Moreover, ever since I did that, when I log back to X11 from Wayland firefox hangs on restore and I loose everything. I did the test twice and both times I could not recover any of my firefox windows. This was a bit of a bummer when it happened first have I to say as I lost a lot of pages! But hey the price to pay when trying things out without saving I suppose.

Comment 3 David Edmundson 2024-09-27 11:03:06 UTC

If there is an issue here it is a Firefox issue. I have not seen it

Comment 4 Gauthier 2024-09-27 12:48:19 UTC

(In reply to David Edmundson from comment #3)
> If there is an issue here it is a Firefox issue. I have not seen it

I'm basically always on wayland now so I can't tell for sure but the last time I tried which was when I first installed plasma 6 it seemed to be working fine. So I reckon we can mark as solved.