Bug 423018

Summary: No transparency in panel when using PRIME render offload
Product: [Plasma] kwin Reporter: Chandradeep Dey <kde>
Component: compositingAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED WORKSFORME    
Severity: normal CC: magiblot, nate
Priority: NOR    
Version First Reported In: 5.19.0   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description Chandradeep Dey 2020-06-15 15:51:43 UTC 
SUMMARY
I have a Intel HD 630 + nvidia 1050 Ti dual GPU laptop.
When using PRIME render offload, the panel, application launcher, and the system tray applets all turn opaque.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 5.7.2-arch1-1
KDE Plasma Version: 5.19.0
KDE Frameworks Version: 5.71.0
Qt Version: 5.15.0
nvidia Version: 440.82
mesa Version: 20.1.1
Xorg driver: modesetting

ADDITIONAL INFORMATION
I tried installing optimus-manager and switching to nvidia only mode. Transparency works fine while using that.

Changing System Settings > Application Style > Breeze (pencil) > Transparency > Slider changes the transparency of things like the context menus. This works right even when using PRIME render offload.
Comment 1 Chandradeep Dey 2020-06-15 16:11:28 UTC 
Update - Workarounds
1) Disabling compositor on startup and enabling it later
2) Switching to XRender backend and switching back to one of the OpenGL backends
Comment 2 magiblot 2020-06-15 20:11:40 UTC 
I think your friend here is the Shift+Alt+F12 shortcut to toggle compositing without having to mess with the settings.
Comment 3 Chandradeep Dey 2020-06-17 19:26:33 UTC 
(In reply to magiblot from comment #2)
> I think your friend here is the Shift+Alt+F12 shortcut to toggle compositing
> without having to mess with the settings.

Yes, that works too
Comment 4 Chandradeep Dey 2020-07-13 17:12:00 UTC 
Update - bug still present with nvidia 450.57 driver


SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 5.7.7-arch1-1
KDE Plasma Version: 5.19.3
KDE Frameworks Version: 5.72.0
Qt Version: 5.15.0
nvidia Version: 450.57
mesa Version: 20.1.3
Xorg driver: modesetting
Comment 5 Chandradeep Dey 2020-08-05 14:57:31 UTC 
Can't replicate after a clean install of Arch, nobody else seems to be affected.