Firefox 89: Text in tabs hard to read

[Narrat]

Firefox 89 introduced some overhaul of its ui. And using the system theme looks like follows:

The Box on the selected tab looks kinda weird. Half applied theme? And this massive height... somewhat lower would imo be nice.
The text on unselected tabs is almost impossible to read. On mouseover of an inactive tab the text is readable but not really pleasant to do so.

Anything that can be done about this?