UI Regression: Inconsistent spacing in focused sidebar items

[fwcd]

Bug Description

Just a tiny thing I've noticed, focusing a sidebar item adds some padding that disappears once the item loses focus:

Expected

Screen.Recording.2023-09-10.at.19.21.24.mov

Current

Screen.Recording.2023-09-10.at.19.24.13.mov

According to my regression finder, this was introduced between 393ddc4 (last good) and 7f79194 (first bad), i.e. in this diff.

cc @ronso0

Version

2.5-alpha-98-gf4692aa5ea (Qt 6.5.2)

OS

macOS 13.5

[ronso0]

Are both videos recorded with Qt6 builds?
Can you reproduce with Qt5? (I can't, using Ubuntu 20.04)

[fwcd]

I can reproduce this with Qt 5.12.5 on the most recent main branch too (on macOS).

[ronso0]

I can't reproduce on main either, I assume it's some margin: 0px; missing 🤷‍♂️
I'll post a test PR soonish.

[ronso0]

Or you try adding

margin: 0px;
padding: 0px;

yourself here

mixxx/res/skins/LateNight/style_palemoon.qss

Lines 2559 to 2566 in 03d0ce7

	WLibrarySidebar::item:selected:focus {
	outline: none;
	border: 0px;
	}
	WLibrarySidebar::item:!selected:focus {
	outline: none;
	border: 1px solid white;
	}

Please check whether it still looks as expected when increasing the library row height in Pref > Interface.

[fwcd]

Unfortunately, neither the QSS patch nor the library row height seem to affect this.

[fwcd]

Did a more fine-grained bisect and found that b576824 introduced the regression.

[fwcd]

Removing border: 0px; from WLibrarySidebar::item:selected:focus fixes it.