Bug 482939 - Screen Layouts Not Remembered
Summary: Screen Layouts Not Remembered
Status: RESOLVED FIXED
Alias: None
Product: KScreen
Classification: Plasma
Component: common (other bugs)
Version First Reported In: 6.0.1
Platform: Arch Linux Linux
: NOR normal
Target Milestone: ---
Assignee: kscreen-bugs-null@kde.org
URL:
Keywords: qt6
Depends on:
Blocks:
 
Reported: 2024-03-09 01:47 UTC by Damon Devitt
Modified: 2024-06-12 15:21 UTC (History)
3 users (show)

See Also:
Latest Commit:
Version Fixed/Implemented In: 6.1.0
Sentry Crash Report:


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Description Damon Devitt 2024-03-09 01:47:12 UTC
SUMMARY
After upgrading to Plasma 6.0.1, my monitor layouts are no longer remembered as they were on Plasma 5. 

Example: I run two 32:9 monitors, and regularly use the split screen function. On Plasma 5, it would automatically switch my display settings back to 5120x1440 with other settings such as layout and refresh rate restored. With Plasma 6, the monitor stays at 2560x1440 and I have to manually go into display settings every time to change it back. 


STEPS TO REPRODUCE
1. Use the split screen option on a monitor that supports it
2. Switch it back to full screen

OBSERVED RESULT
The screen settings stay at the split 2560x1440

EXPECTED RESULT
The screen layout returning to what it was prior to using the monitor's split screen function

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Arch Linux / Plasma 6.0.1
KDE Plasma Version: 6.0.1
KDE Frameworks Version: 6.0.0 
Qt Version: 6.6.2
Comment 1 Nate Graham 2024-03-11 22:11:31 UTC
> and regularly use the split screen function
What is the split screen function?

Does the issue reproduce in a new clean user account using the Wayland session?
Comment 2 Damon Devitt 2024-03-12 02:11:42 UTC
(In reply to Nate Graham from comment #1)
> > and regularly use the split screen function
> What is the split screen function?
This is a feature on many ultrawide monitors that splits the monitor into two separate output devices. From the PC's perspective, the monitor's resolution just changes from 5120x1440  to 2560x1440 and vice versa. It triggers a disconnect/reconnect when this is occurring. 

> Does the issue reproduce in a new clean user account using the Wayland
> session?
I won't be able to test this with a fresh account for a few days and will check back in once I've done so, but immediately after upgrading to Plasma 6 I cleared out all of my Plasma/KDE configs to start fresh. I should also mention this was occurring on Wayland with an AMD 6900XT and I did not test X11.
Comment 3 Nate Graham 2024-03-13 19:23:10 UTC
So you have two ultrawide 5120x1440 monitors, and you use the split screen feature to make each of them get exposed to the system as two 2560x1440 monitors, so Plasma and KWin see four monitors instead of two? Do I have that right?

And then when you disable this feature on either of the monitors under Plasma 6, they get reset to 2560x1440 instead of 5120x1440? Do I have that right as well?
Comment 4 Bug Janitor Service 2024-03-28 03:46:51 UTC
Dear Bug Submitter,

This bug has been in NEEDSINFO status with no change for at least
15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
tracker maintenance, if the bug is still in NEEDSINFO status with
no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

If you have already provided the requested information, please
mark the bug as REPORTED so that the KDE team knows that the bug is
ready to be confirmed.

Thank you for helping us make KDE software even better for everyone!
Comment 5 Bug Janitor Service 2024-04-12 03:48:00 UTC
This bug has been in NEEDSINFO status with no change for at least
30 days. The bug is now closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

Thank you for helping us make KDE software even better for everyone!
Comment 6 Damon Devitt 2024-05-28 02:02:22 UTC
Sorry for the extremely late reply. A combination of things including a PC failure had me forgetting about this until now. On the plus side, the new laptop meant I was able to test this on a fresh install with an Intel GPU instead of AMD. The same thing still happens on the new system. 

Updated version numbers since it's been a couple months:
Linux/KDE Plasma: Arch Linux / Linux-Zen 6.9.3
KDE Plasma Version: 6.0.5
KDE Frameworks Version: 6.2.0
Qt Version: 6.7.1

(In reply to Nate Graham from comment #3)
> So you have two ultrawide 5120x1440 monitors, and you use the split screen
> feature to make each of them get exposed to the system as two 2560x1440
> monitors, so Plasma and KWin see four monitors instead of two? Do I have
> that right?
Correct. It just reports to the system that the max output resolution of each port is 2560x1440 when I enable it

> And then when you disable this feature on either of the monitors under
> Plasma 6, they get reset to 2560x1440 instead of 5120x1440? Do I have that
> right as well?
This is partially correct. It just stays at whatever setting I had it on previously. When I switch the monitor to 2560x1440 mode (from the monitor's menu), it flips to the lower resolution just fine, but when I switch it back to 5120x1440 it's still at 2560x1440 when it reconnects. I'm not sure if Plasma was assuming it was a different monitor on 5.27 or what could have caused this to change on Plasma 6.
Comment 7 Zamundaaa 2024-06-12 15:21:06 UTC
Plasma 5 / KScreen remembered output settings based on the whole hash of all output related information, which did cause it to identify the split screen monitor as a different display, and by chance made this work correctly.
In Plasma 6 / KWin, output settings are remembered for the actual display instead, so the 2560x1440 setting is remembered even once the bigger mode is available again.
6.1 remembers intentionally set modes from those automatically chosen modes separately though, so this will work correctly there