Bug 515576

Summary: Qt6: Resizing the canvas widget sometimes flickers
Product: [Applications] krita Reporter: Freya Lupen <penguinflyer2222>
Component: OpenGL CanvasAssignee: Krita Bugs <krita-bugs-null>
Status: REPORTED ---    
Severity: normal Keywords: regression
Priority: NOR    
Version First Reported In: 6.0.0-beta1   
Target Milestone: ---   
Platform: macOS (DMG)   
OS: macOS   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: Flickering on canvas widget resize

Description Freya Lupen 2026-02-05 21:33:34 UTC
Created attachment 189257 [details]
Flickering on canvas widget resize

SUMMARY
When resizing the canvas widget (such as by resizing a docker), sometimes a frame or two of the image on canvas disappears (while leaving the canvas background visible), causing flickering.

It happens when canvas graphics acceleration is on. I don't know whether it happens on platforms other than macOS.

This doesn't happen on Qt5.

STEPS TO REPRODUCE
1. Open a document.
2. Resize a docker so that the canvas widget resizes, watch for flickering.

OBSERVED RESULT
Random missing frame of the image

EXPECTED RESULT
Normal image frames 

SOFTWARE/OS VERSIONS
Krita 6.0.0-beta1
macOS Sequoia

ADDITIONAL INFORMATION
See attached video at around :02, :04, :06.