As far as what caused the problem in the first place, i think it was likely along the lines of the third known cause that CerealLover listed in one of the threads you posted here for me to consider:
- You enabled ‘Allow Google login buttons on third party sites’ especially for the urls: https://[*.]firebaseapp.com and https://accounts.google.com
I think this because these same two websites popped up in the new profile I created.
I wonder if I inadvertently selected this on a pop-up that I might not a have read thoroughly in trying to get to my next task. I’m often a bit inpatient when I get one of those pop-ups asking if the site can have my location data. I just changed the Brave setting to not to be asked. Maybe this will help avoid the unwanted cookie problem in the future.