Every render event(i.e. F12 or ⌃ Ctrl + F12) results in appearance of the panel marked on the image below.
Stretching it using mouse helps remove it. In other words, it disappears if stretched.
Also, it's worth to mention that clicking on the arrow, located on the panel on the middle-top area of the image, does nothing.
The image:

It nearly prevents clicking on the tabs and also hides them:

Blender: 2.91.2, 5be9ef417703, master, 2021-01-19 16:15, as found on the splash screen.
OS: Win10x64
I'd appreciate for the suggestion.
F12key is being hit, it seems. The question you mentioned looks quite different. There's no oversized panel, but an additional, empty one. I'm sorry, but why would a GPU driver be related to the UI element appearance? – Artfaith Jan 28 '21 at 07:13