Does this answer your question? [Menu bar and toolbar of few applications are very tiny in ubuntu 20.04](https://askubuntu.com/questions/1260560/menu-bar-and-toolbar-of-few-applications-are-very-tiny-in-ubuntu-20-04)
– vanadiumSep 04 '20 at 10:40
See duplicate question. You experience a bug in mutter. There is a temporary workaround in the question linked.
– vanadiumSep 04 '20 at 10:41
@vanadium thx. It shoud be Nvidia driver bug. Using Nouveau and `xrender` can temporarily solve it.
– fishymanSep 04 '20 at 11:15