Bug 498553 - Windows get resized when turning multiple monitors off and then back on again
Summary: Windows get resized when turning multiple monitors off and then back on again
Status: REPORTED
Alias: None
Product: kwin
Classification: Plasma
Component: multi-screen (other bugs)
Version First Reported In: 6.2.5
Platform: NixOS Linux
: NOR normal
Target Milestone: ---
Assignee: KWin default assignee
URL:
Keywords: multiscreen
Depends on:
Blocks:
 
Reported: 2025-01-12 10:31 UTC by Arne Keller
Modified: 2025-01-17 12:16 UTC (History)
1 user (show)

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


Attachments

Note You need to log in before you can comment on or make changes to this bug.
Description Arne Keller 2025-01-12 10:31:49 UTC
SUMMARY
Some windows get resized when turning on all monitors after leaving both monitors off for some time.

STEPS TO REPRODUCE
1. Connect two monitors via DP (secondary) and HDMI (primary)
2. Start a Qt app (e.g. KeePassXC) and a GTK app (e.g. Firefox / Thunderbird)
3. Turn off both monitors
4. Wait
5. Turn on both monitors

OBSERVED RESULT
KeePassXC is resized. Usually smaller than before.
Firefox, Thunderbird keep previous size.

EXPECTED RESULT
All windows keep their size.

WORKAROUND
Use a KWin script to resize windows to their expected size.

SOFTWARE/OS VERSIONS
Operating System: NixOS 24.11
KDE Plasma Version: 6.2.5
KDE Frameworks Version: 6.8.0
Qt Version: 6.8.0
Kernel Version: 6.6.69 (64-bit)
Graphics Platform: X11
Graphics Processor: AMD Radeon RX 5600 XT
Manufacturer: Micro-Star International Co., Ltd.
Product Name: MS-7C37
System Version: 3.0

ADDITIONAL INFORMATION
Related KDE Discuss thread: https://discuss.kde.org/t/some-windows-resize-when-i-turn-on-off-a-second-monitor/25220
Comment 1 Nate Graham 2025-01-13 21:49:52 UTC
Can you reproduce it with only a single monitor, if you turn it off and then back on again? In other words, is the triggering condition actually the act of going down to 0 active screens?
Comment 2 Arne Keller 2025-01-13 21:53:56 UTC
I'll check. Though I don't think I changed anything about my Plasma setup when I installed the second monitor. (The issue only started occuring once I started using two monitors.)
Comment 3 Arne Keller 2025-01-17 12:16:41 UTC
> Can you reproduce it with only a single monitor, if you turn it off and then back on again? In other words, is the triggering condition actually the act of going down to 0 active screens?

I could not reproduce the issue with only one connected monitor.