Heya, I’ve had this same issue with my Roblox Studio; same crash message and everything.
I did find a way around this crash, however I don’t know if it will work for you as well.
But hey, gotta give it as a potential solution in case it does work.
I first clicked on the X of that popup, and confirm to close Studio.
I re-open Studio for the same game. This should give the option between Login via Browser and Login via Studio.
I click on Login via Studio.
I log in (using the username and password input), and after Studio freezing for a minute or so, it loads the game just fine.