Bug 457214

Summary: Xournal++: Highlighted cursor shows a flashing rectangle and darkened highlighting >= 150% scaling
Product: [Plasma] kwin Reporter: postix <postix>
Component: wayland-genericAssignee: KWin default assignee <kwin-bugs-null>
Status: REPORTED ---    
Severity: normal CC: nate, postix
Priority: NOR Keywords: wayland
Version: 5.27.4   
Target Milestone: ---   
Platform: openSUSE   
OS: Linux   
See Also: https://bugs.kde.org/show_bug.cgi?id=465891
https://bugs.kde.org/show_bug.cgi?id=455898
Latest Commit: Version Fixed In:
Sentry Crash Report:
Attachments: Screen recording

Description postix 2022-07-27 18:11:22 UTC
Created attachment 150952 [details]
Screen recording

STEPS TO REPRODUCE
1.  Open Xournal++ 1.1.1+dev (b5da66c9)
2.  File -> Preferences -> View: "Highlight cursor position", "Radius 30", "Border width: 0", Cursor Icon for Pen "Small dot"
3.  Draw something with your tablet or mouse in Xournal++ using the pen tool

OBSERVED RESULT
Using 200% scaling, the highlighting, which is a bright yellow by default, becomes a dark yellow and every now and then a rectangle appears at the cursor within the highlighting. I could not observe this when changing the scaling to something lower, like 100% or 125%.

Please see the bad screen recording. I had to use my phone since OBS studio did not record the highlighting.

I could not observe this using the nightly Appimage [1]  on Fedora 36 with Gnome 42 Wayland and 200% scaling, corresponding to the same git commit as my local build on TW. So I guess it could be a kWin issue.

Though I could neither trigger it with the stable version of Xournal++ 1.1.1 from the openSUSE TW repo. So maybe a Xournal++ issue after all? 

Hopefully someone can reproduce it.

[1] https://github.com/xournalpp/xournalpp/releases/tag/nightly


SOFTWARE/OS VERSIONS
Operating System: openSUSE Tumbleweed 20220725
KDE Plasma Version: 5.25.3
KDE Frameworks Version: 5.96.0
Qt Version: 5.15.5
Kernel Version: 5.18.11-1-default (64-bit)
Graphics Platform: Wayland
Graphics Processor: AMD Radeon RX 580 Series
Comment 1 postix 2022-07-27 18:17:02 UTC
It happens for all scaling factors, starting at 150% and I also could only reproduce it on Wayland.