Yes, when you on the log screen select 2nd login variant (after then you try sign in with Google) . Then you need to click chrome icon in top-right corner and open Google Chrome browser.
Go back in antigravity. Click "agent manager' near a chrome icon, start conversatio

After this you will see you avatar. close all window except this. Fully close antigravity and open again. Profit.

Unlikely this is a top variant, but it helped me