Social (FB) login module
Since CJforum supports social login, I suggest to develop a suitable Joomla! module to provide the user a login form.
The scenario would be the following:
- the user logins his social network in the browser
- the user opens a new tab in the same windows
- the user enters the URL of the forum
- the users click the relevant sso object (e.g. FB button)
- if the user is registered he logins; if not he is registered (ideally with administrator approval and/or guest status)