Bug 438722

Summary:	Desktop effects disabled on login if Background Contrast disabled
Product:	[Plasma] kwin	Reporter:	Martin Corley <Martin.Corley>
Component:	effects-various	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UNMAINTAINED
Severity:	normal	CC:	Martin.Corley, nate
Priority:	NOR
Version First Reported In:	5.22.1
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Martin Corley 2021-06-16 09:06:58 UTC

Desktop effects are disabled on login (but can be restored) if the Background Contrast effect is disabled


STEPS TO REPRODUCE
1. In system settings, disable Workspace Behaviour->Desktop Effects->Background Contrast
2. Logout (reboot), Log in

OBSERVED RESULT
Desktop Effects are disabled.  Notification explains that they have been "disabled by an app".  They can be re-enabled using ALT-Shift-F12.

EXPECTED RESULT
Desktop Effects remain enabled

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: Arch / 5.12.10-zen
(available in About System)
KDE Plasma Version: 5.22.1
KDE Frameworks Version: 5.83.0
Qt Version: 5.15.2

ADDITIONAL INFORMATION
NB., this is under X11 with compositor set to OpenGL 3.1.  Most other options are default or near-default (Breeze Dark theme).

Comment 1 Nate Graham 2021-06-16 17:35:03 UTC

Cannot reproduce.

Comment 2 Martin Corley 2021-06-16 20:05:14 UTC

On further investigation, this only occured when I had an external monitor attached to my laptop (intel graphics, i915).

In a live plasma session, adding _or_ removing the external monitor reliably suspends desktop effects, but _only_ if Background Contrast is disabled.  Apologies for the misreport earlier.

Comment 3 David Edmundson 2023-09-06 10:38:09 UTC

This bug was reported against an outdated version of KWin. We have made many changes since the. 
If the issue persists in newer versions can you reopen the bug report updating the version number.