Sign-in could not be completed — try email and password
Social login redirected with an unmapped or unknown oauth_error. UI falls back to Sign-in could not be completed. Try again or use email and password. (auth.oauthGeneric).
Why this happens
translateOAuthError did not recognize the code/message. Can also surface for odd provider failures. More specific siblings: cancelled, disabled, invalid session, provider failed (Could not complete sign-in with the provider).
Diagnose and fix
1. Retry social sign-in once; or use email and password.
2. Admin: check Social login credentials and OAuth redirect URI.
3. Read the login URL oauth_error param for a more specific code if present.
4. Distinct from Could not complete sign-in (finalize/session path).