This happens to me almost anytime I use gh.
I happened also on my laptop so 2 different computers, so I think its related to some other software I have on my pc (just guessing here not really sure).
Anyway the problem is with input focus, after a while grasshopper does not get keyboard inputs anymore, these are redirected to the rhino prompt.
This makes it impossible to work , ctrl-c, ctrl-v go to rhino, editing panels does not work and so on, a long list of things impossible to do.
Does anybody have an Idea on how to understand why and how to find a fix ?