Bug 499035

Summary:	New account creation on Wayland overrides screen scaling
Product:	[Plasma] kwin	Reporter:	amdfan12
Component:	general	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED INTENTIONAL
Severity:	normal	CC:	kde, nate
Priority:	NOR
Version First Reported In:	6.2.5
Target Milestone:	---
Platform:	Other
OS:	Linux
See Also:	https://bugs.kde.org/show_bug.cgi?id=499034
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description amdfan12 2025-01-23 03:11:08 UTC

SUMMARY
When creating a new account on a Wayland session, the created account will use a different screen scaling value than the "creating" account. This does not create a consistent user experience on a given system/configuration

STEPS TO REPRODUCE
1. Acquire 27" 2560x1440 monitor
2. Set resolution to 2560x1440
3. Set screen scaling to 100%
4. Create new user account, then login

OBSERVED RESULT
New account will use 125% screen scaling

EXPECTED RESULT
New account should use 100% screen scaling for a consistent user experience. This reflects the behavior in other operating systems, such as Windows.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Fedora 41/OpenSUSE Tumbleweed
KDE Plasma Version: 6.2.5
KDE Frameworks Version: 6.10
Qt Version: 6.8.1

ADDITIONAL INFORMATION

Comment 1 Nate Graham 2025-01-23 15:55:05 UTC

It's intentional that KWin (not Plasma) does its best to use a sane scale factor for new accounts, which depends on the screen's resolution and physical size.

Size of items on screen being a subjective preference, it's possible to override the default scale that KWin chooses, which is why this is user-customizable on a per-user basis. Given that a new user account may be used by a different person, it's reasonable to expect that person might have preferences that differ, which means it doesn't make sense to inherit the scale value set by a different user on the same machine.