FB Valid OAuth redirect URIs for cjforum

What is a valid  OAuth redirect URI suitable for the login FB app?

The example templale

 https://www.yourdomain.com/index.php?option=com_jfbconnect&task=authenticate.callback&provider=facebook

doesn't seem to work ("URL Blocked: This redirect failed because the redirect URI is not whitelisted in the app’s Client OAuth Settings. Make sure Client and Web OAuth Login are on and add all your app domains as Valid OAuth Redirect URIs.")

(I've tried with/without www, index.php et c. )