Rotating wait symbol in Project list whenever typing

Hello,

Whenever I type anything in any file in IntelliJ (it can even be a plain text file in which it shouldn't do any parsing), there is a rotating "wait" symbol in the top right part of the Project list (the list on the left that shows all files).

This is very annoying, distracting, and gives the feeling that typing goes very sluggish.

Is there a way to get rid of this?

What are good strategies for me to find out what IntelliJ is actually doing and why it's showing that indicator?

Thanks!