Bug 454604

Summary:	Display scale "lost" when plugging/unplugging external monitor
Product:	[Plasma] KScreen	Reporter:	Iyán M. V. <me>
Component:	common	Assignee:	kscreen-bugs-null <kscreen-bugs-null>
Status:	RESOLVED FIXED
Severity:	normal	CC:	nate
Priority:	NOR
Version First Reported In:	5.25.90
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Iyán M. V. 2022-05-30 12:01:47 UTC

SUMMARY
Sometimes (I can reproduce with an external HDMI TV, but not with a monitor connected to a USB-C docking station) the scale factor from the Display Configuration, is not respected after connecting (and/or disconnecting) an external display.

Setting is not modified. Rebooting does not solve the issue. Only modifying the value to a different one, saving, and then going back to the desired value restores the settings.

P.S. Thank you for the great work doing for this and previous releases. I have now changed to Wayland and it feels great!

STEPS TO REPRODUCE
1. Configure some scale (e.g. 125%)
2. Connect an external monitor (and use the extend mode)
3. Remove external monitor

OBSERVED RESULT
Scale value still shows 125% but it is in fact back to 100%. Rebooting does not solve the issue. Configuration still shows a scale of 125% but in reality is 100%. To go back to 125%, you can change to 150% save, and then go back to 125%.

EXPECTED RESULT
Scale factor should always be respected for the built-in screen and not changed no matter if an external display is attached. Also, in any case, detaching the external display, should restore previous state.

SOFTWARE/OS VERSIONS
Operating System: Arch Linux
KDE Plasma Version: 5.24.90
KDE Frameworks Version: 5.94.0
Qt Version: 5.15.4
Kernel Version: 5.18.0-arch1-1 (64-bit)
Graphics Platform: Wayland
Processors: 8 × 11th Gen Intel® Core™ i5-1135G7 @ 2.40GHz
Memory: 15.4 GiB of RAM
Graphics Processor: Mesa Intel® Xe Graphics
Manufacturer: LENOVO
Product Name: 20XYCTO1WW
System Version: ThinkPad X1 Yoga Gen 6

Comment 1 Iyán M. V. 2022-09-20 10:04:35 UTC

I can observe this with Plasma 5.26 Beta as well.

Comment 2 Nate Graham 2022-11-10 17:58:18 UTC

On Wayland, scale is per-screen, not global. Can you clarify which screen is getting its scale reset? The internal laptop screen, or the external screen?

Comment 3 Bug Janitor Service 2022-11-25 05:21:49 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 4 Bug Janitor Service 2022-12-10 05:18:29 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 5 Iyán M. V. 2023-01-26 11:41:02 UTC

I just saw this was closed automatically and I forgot to answer last question from Nate. Anyways, after the big refactor for 5.27, this never happended again.