Bug 499224

Summary: Cannot zoom canvas with mouse wheel while pen is hovering
Product: [Applications] krita Reporter: cromachina
Component: UsabilityAssignee: Krita Bugs <krita-bugs-null>
Status: REPORTED ---    
Severity: normal    
Priority: NOR    
Version First Reported In: 5.2.6   
Target Milestone: ---   
Platform: NixOS   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description cromachina 2025-01-28 02:32:26 UTC 
SUMMARY
I draw with my left hand, and as a consequence, I use my mouse wheel separately with my right hand. I notice that if I'm hovering my pen over my screen tablet, the mouse scroll stops working until I stop hovering my pen. I use this a lot to control zooming in other applications, like SAI and CSP. It's a bit annoying to have to keep lifting my hand away from the screen tablet to allow mouse wheel scrolling.

STEPS TO REPRODUCE
1. Hover your tablet pen over the canvas.
2. Try to scroll your mouse wheel to change zoom levels.

OBSERVED RESULT
Nothing happens.

EXPECTED RESULT
Zoom happens at the pen's hover position.

SOFTWARE/OS VERSIONS
Operating System: NixOS 25.05
KDE Plasma Version: 6.2.5
KDE Frameworks Version: 6.9.0
Qt Version: 6.8.1
Comment 1 cromachina 2025-10-09 00:27:24 UTC 
This appears to be related to using X11 in combination with Qt. A similar issue happens with Drawpile https://github.com/drawpile/Drawpile/issues/1529

Updated kinfo:
Operating System: NixOS 25.11
KDE Plasma Version: 6.4.5
KDE Frameworks Version: 6.18.0
Qt Version: 6.9.2
Kernel Version: 6.16.9-zen1 (64-bit)
Graphics Platform: X11
Processors: 24 × AMD Ryzen 9 3900X 12-Core Processor
Memory: 64 GiB of RAM (62.7 GiB usable)
Graphics Processor: AMD Radeon RX 7900 XTX
Comment 2 cromachina 2025-10-20 14:46:03 UTC 
I was able to make this happen with a minimal Qt program and filed a bug with Qt: https://bugreports.qt.io/browse/QTBUG-141252