SOME users get FB Login Error.
1) Failed users can't Register or login with FB button (a few others can without a problem)
2) Failed users get the typical " "App Not Setup: The Developers of this app..." error with no further details from FB
3) I have the latest JFC (downloaded yesterday) am running on Joomla 3.4 and Jomsocial.
4) Same problem happens if I have Jomsocial integration turn on (and plugins enabled) or turn off with plugins disabled.
5) Autotune says everything is fine, your test and site check features pass, even FB says the apps seems to be set up correctly.
6) Same problem happens with Chrome or IE, with history/cache emptied or not.
7) The Failed users are consistently failing (never can reg or login) and the successful users (like me) can always login or register.
Help