main ← no-username-fallback
merged 10:02AM - 08 Jan 26 UTC
When `use_email_for_username_and_name_suggestions` is disabled, the username sug…gester was falling back to generic usernames like "user1", "user2", etc. These suggestions are rarely helpful as they create indistinct usernames that users often accept without modification, resulting in forums populated with "user763", "user764", etc.
This change adds an `allow_generic_fallback` option to `UserNameSuggester.suggest()`. When set to false, it returns nil instead of falling back to generic "userN" usernames. The OAuth authentication flow now uses this option, leaving the username field blank so users must choose their own meaningful username.
Ref - https://meta.discourse.org/t/391542
