With Recover Accounts Elsewhere, you can add an extra security factor to your GitHub account in case you lose access to your two-factor authentication method or recovery codes.
Recover Accounts Elsewhere lets you associate your GitHub with your Facebook account. You can store an authentication credential in the form of an account recovery token for your GitHub account with Facebook.
If you lose access to your GitHub account because you no longer have access to your two-factor authentication method or recovery codes, you can retrieve your account recovery token from the recovery provider to help prove that you're the owner of your GitHub account.
After you retrieve your token, GitHub Support may be able to disable two-factor authentication for your account. Then, you can provide or reset your password to regain access to your account.
Your account recovery token is valid for a year or until you use it. If you retrieve your token or your token expires, you should generate and store a new token.
When you generate or retrieve an account recovery token, an event is added to your account's audit log. For more information, see "Reviewing your security log."