Deck Browser (main window) shaky when collapsing/uncollapsing

[jcznk]

I did some brief testing, and it looks like the last version without the issue is 2.1.49. Since it is also the last version without the Qt5/Qt6 split, I thought that might be related, but the issue seems to occur on both Anki 24.06.3 Qt5 and Anki 24.06.3 Qt6. This mostly happens when the Deck/Subdecks structure is complex. The tests below were performed using the same collection. The difference in the amount of 'due' cards is because review limits were handled differently before Anki 2.1.55.

Anki 2.1.49, Windows 10 -> no issue

2.1.49.mp4

Anki 24.06.3 qt6 -> the Deck Browser is shaky when collapsing/uncollapsing

24.06.3.qt6.mp4

[jcznk]

I did some further testing, and the "shaking" sometimes occurs on version 2.1.49 as well, though it is somewhat harder to trigger.