I don’t know there is a bug here but it doesn’t seem to work well for me.
In the config file it is set correctly:
$config['FAL_user_name_duplicate_validation'] = 'trim|required|xss_clean|username_check|username_duplicate_check';
But i still can register several users with the same username, it also does absolutly not check the username field, and didn’t trim it.
Can somebody help me fix it ?