Yesterday I noticed this issue but it may have been there for a number of days.
Popup boxes aren't scaling, and there is no way to expand them. As a result i'm unable to view the content completely, making a number of functions quite challenging.
Is this related to a PowerBi update or a Windows Update?
It works well on my side.
Power bi desktop Version: 2.86.902.0 64-bit (October 2020)
Microsoft Windows version 2004
if you could uninstall and reinstall the power bi desktop, and also restart the computer then try it again.
Same issue persists after updates and reinstalls.