Panel spacing style changes not applied until mouse-over in 3.34
In gnome-shell 3.34, I've noticed behaviour like the following using extensions that modify spacing of panel items. The spacing changes are not reflected upon changing them, or upon login or resume from suspend until mousing over the panel, at which point items jump around. The issue did not occur in gnome-shell 3.32. Here is an example with the "dash to panel" extension:
With no extensions running the issue is reproducible by entering the following into looking glass:
and then mouse over the system menu. It will jump to the left upon mouse-over.
Some discussion of the issue in the dash-to-panel issue tracker.
I'm on Arch Linux with gnome-shell and mutter 3.34. I noticed this problem first arise whilst I was on gnome-shell 3.32 with some backported performance patches during the 3.34 development cycle. So it was one of those patches that introduced the issue - you can see the list of patches that were merged into this package here