Flatpak Qt popup menus are constrained to left half of the screen under fractional scaling

[effectsbot]

Hyprland version

v0.49.0

Regression

No.

Describe the bug

Flatpak applications using Qt have their popup menus constrained to the left half of the screen when using fractional scaling. For example, when right-clicking on the right half of OBS's window, the popup menu will not appear on the pointer as expected. Instead the menu will appear on the edge of the left half of the screen.

This does not affect Qt applications that are installed natively and is also reproducible on Sway.

Video_2025-07-14_17-10-43.mp4

Reproduction steps

1. Set your monitor's scaling to a fractional value (e.g. 1.25).
2. Install OBS as a flatpak, then right-click on the right half of its window.

System info and log

systeminfo.txt
hyprland.log

[vaxerski]

This does not affect Qt applications that are installed natively and is also reproducible on Sway.

Then it's likely it's a qt bug

[effectsbot]

Bit late, but I filed a bug report on KDE's bugtracker about this. Hopefully this will resolve the issue.