Qt for Python (PySide/Shiboken)

I had another go and tried running the Python code using PySide 6.8.0.2 directly on Windows 11 without packaging it through PyInstaller. The same exact problem is present. No issues if the style is set to "Fusion": https://pasteboard.co/pt2v4i1unjku.png Even though I must admit it looks quite bad in Windows 11...