QSpinBoxes take too much vertical space if an application-wide style sheet is set

[l3u_]

Hi all,

I noticed a quite weird bug: If I set an application-wide style sheet, all QSpinBoxes take too much vertical space. It doesn't matter what the style sheet contains.

Without an application-wide style sheet, a QLineEdit and a QSpinBox have the same height:

But after setting an application-wide style sheet (in this case a completely unrelated QGroupBox { font-weight: bold; }), the QSpinBox is rendered too high:

This seems to be a KDE Breeze bug, as it does not happen when using Fusion. I filed a respective KDE bug already (also containing a minimal example for reproducing the issue).

The interesting part is: It seems only to happen using Qt 6.8.2, and not yet if 6.8.1 is used. At least, I didn't see this on my Gentoo machine running 6.8.1, but on my Artix notebook running 6.8.2 – but not on another Artix machine still on 6.8.1.

I'd like to not only complain about this, but to help fixing it. Can somebody of the pros give me a hint which change in Qt may have caused this? I have no idea where I should start to search …

Thanks in advance for all help!

[Christian Ehrlicher]

I would say it's because of https://codereview.qt-project.org/c/qt/qtbase/+/601315 and https://codereview.qt-project.org/c/qt/qtbase/+/613831
Maybe breeze had some kind of workaround for this which is now doing wrong calculations.

[l3u_]

Thanks a lot for the quick follow-up! I'll provide this info in the KDE bug.

Hopefully, we'll get that fixed soon …