When I click to Register or Sign In using Gerrit Code Review, I get this error: Provider is not supported, or was incorrectly entered.
And when I enter the URL into the OpenID field manually, it takes me to a Google page stating: The page you requested is invalid.
Any clue what's happening here?
EDIT: Upon further investigation, I realized that if I change the provided URL in the OpenID field to http rather than https, it will redirect me to Google properly and ask me to approve. However, on the redirect back to Gerrit, nothing seems to have happened. I tried registering/signing in multiple times and to no effect.
I've also looked in the MySQL database to see if any data was being stored, and there doesn't appear to be.
EDIT 2: I've now submitted a bug report to Gerrit.
EDIT 3: Answered. I'd have done well to read the previous bug reports a bit more closely. My sysadmin fu is also severely lacking. Nonetheless, this is solved as a duplicate of another bug and is a Debian issue; see below.