Getting white borders on dropdown menu/ right click menu

[Nakkhatra]

OS: Ubuntu 20.04
What it looks like:

My current setup of themes and extensions:

I previously used this theme without issues like this on Ubuntu 20.04. This is a newly installed OS on my new SSD and facing this. I have the same issue if I use the nordic dark shell theme too. This is not present only if I use the WhiteSur Dark shell theme.

[Nakkhatra]

Since I mentioned the nordic dark, I don't have the issue with nordic dark, rather with Nordic darker v40 and that too is not as annoying as this one. That looks like this: