Hi! Do you remember which grass model exactly, or is it all of them?
It's highly unusual for something like this to crash Unity, I'd like to test it out myself, as I tested it on an older Unity version previously
Hi! You can try reinstalling the Unity Editor. I used to get crashes as well in different circumstances, and reinstalling the editor helped to solve the issue for me, so it might work for you as well!
There's a link to my discord community server on my main itch.io page, you can DM me directly from there!