Bug 512580

Summary: Unusual dark artifacts produced around edges of desktop plasmoids
Product: [Plasma] plasmashell Reporter: doncbugs
Component: ContainmentAssignee: Plasma Bugs List <plasma-bugs-null>
Status: REPORTED ---    
Severity: minor CC: kdedev, nate, notmart
Priority: NOR    
Version First Reported In: 6.5.3   
Target Milestone: 1.0   
Platform: CachyOS   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: The edges have a dark gradient and the bottom corners are square

Description doncbugs 2025-11-25 03:13:43 UTC
Created attachment 187145 [details]
The edges have a dark gradient and the bottom corners are square

SUMMARY
Plasmoids on the desktop with blurred backgrounds drawn by the plasma style's widgets have unusual dark gradients around the edges. Additionally, the bottom appears to have sharp corners in certain configurations.

STEPS TO REPRODUCE
1. Set your plasma style to a theme that raises visibility (I used Sumac Night Molten Glass)
2. Add a plasmoid that has a drawn background to the desktop (I used Weather Report)

OBSERVED RESULT
The plasmoid has a sharp dark gradient on all 4 sides and the bottom corners are sharp.

EXPECTED RESULT
The plasmoid should look similar to the panel's plasmoids, such as Kickoff, and not have dark gradients, nor sharp bottom corners.

SOFTWARE/OS VERSIONS
Operating System: CachyOS Linux 
KDE Plasma Version: 6.5.3
KDE Frameworks Version: 6.20.0
Qt Version: 6.10.0
Kernel Version: 6.17.8-2-cachyos (64-bit)
Graphics Platform: Wayland

ADDITIONAL INFORMATION
I am wondering if there is a quirk in how the bottom corners are calculated that causes this. The dark gradients sort of look like a mask mismatch.
Comment 1 Nate Graham 2026-01-05 20:30:40 UTC
I couldn't find the "Sumac Night Molten Glass" theme on store.kde.org, but I tested with "Sumac Day". The darkened inner edges are just Bug 512579. The square glitches in the bottom corners are something I can't reproduce.

Is this a theme-specific issue in your testing?
Comment 2 doncbugs 2026-01-12 03:13:32 UTC
This is theme specific, but my suspicion is that it may tied to a configuration rather than the theme, as to my knowledge, all elements for an appropriate mask are present and the file itself is an almost identical copy of the dialogs assets that work fine.

(In reply to Nate Graham from comment #1)
> I couldn't find the "Sumac Night Molten Glass" theme on store.kde.org, but I
> tested with "Sumac Day". The darkened inner edges are just Bug 512579. The
> square glitches in the bottom corners are something I can't reproduce.

Unfortunate, I thought I had made the theme fairly discoverable. Here is the link: https://store.kde.org/p/2321401/