Bug 433789

Summary:	Windows maximized on a second monitor are moved to the primary monitor when the monitor goes off
Product:	[Plasma] kwin	Reporter:	Miguel Rozsas <miguel>
Component:	core	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED FIXED
Severity:	normal	CC:	nate
Priority:	NOR	Keywords:	usability
Version First Reported In:	5.21.0
Target Milestone:	---
Platform:	openSUSE
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Miguel Rozsas 2021-03-01 12:00:47 UTC

SUMMARY

In a dual monitor setup, the windows maximized on the second monitor are moved to the primary monitor when the second monitor goes off and goes on again.
The windows that are not maximized on the second monitor or any windows in the first monitor are not affected. They remain where it are supposed to be.

In general, the monitors goes off as result of the automatic lock screen followed by a long period (15min) of inactivity, but it happens manually. I mean, turn the second monitor off by the monitor switch and turn it on again after a short period (seconds).

STEPS TO REPRODUCE
1. In a dual monitor setup, place windows on the first and second monitor. Then maximize some windows, specially on the second monitor.
2. Turn the second monitor off by pressing its power off switch.
3. Wait a few seconds. Turn the second monitor on again. You see the maximized windows placed on the second monitor to show up on the first monitor.

OBSERVED RESULT
The maximized windows placed on the second monitor are showed now on the first monitor.
The maximized windows on the first monitor are not affected.
Any non maximized window in any monitor are not affected.

EXPECTED RESULT
Any windows must stay in its the original place.

SOFTWARE/OS VERSIONS
Operating System: openSUSE Tumbleweed 20210220
KDE Plasma Version: 5.21.0
KDE Frameworks Version: 5.79.0
Qt Version: 5.15.2
Kernel Version: 5.10.16-1-default
OS Type: 64-bit
Graphics Platform: X11
Processors: 8 × Intel® Core™ i7-3770 CPU @ 3.40GHz
Memory: 14.6 GiB of RAM
Graphics Processor: GeForce GTX 970/PCIe/SSE2

ADDITIONAL INFORMATION
This bug happens since KDE 5.20 at least. Its not new on KDE 5.21.

Comment 1 Miguel Rozsas 2021-04-14 14:57:58 UTC

This bug was fixed somehow and it does not manifest itself anymore, probably it was fixed in some iteration of kde 5.21 updates.

My system, currently is running:

Operating System: openSUSE Tumbleweed 20210330
KDE Plasma Version: 5.21.3
KDE Frameworks Version: 5.80.0
Qt Version: 5.15.2
Kernel Version: 5.11.6-1-default
OS Type: 64-bit
Graphics Platform: X11
Processors: 8 × Intel® Core™ i7-3770 CPU @ 3.40GHz
Memory: 14.6 GiB of RAM
Graphics Processor: GeForce GTX 970/PCIe/SSE2