I have a local account registered on this website.
I have also a facebook account , the facebook email is the same that I've given in this website.
If I try to login to this website with Facebook, I cannot login because "Email already belongs to an account".
OK.
I then want to try to log in with another facebook account.
When I click on the button, the pop up login frame opens and suddenly disappears.
If I check the Chrome Developers tool, I can find this error :
Blocked a frame with origin "https://www.facebook.com" from accessing a frame with origin "http://static.ak.facebook.com". The frame requesting access has a protocol of "https", the frame being accessed has a protocol of "http". Protocols must match.
I can try again, but the facebook login is not available anymore.
(I have to clear the browser cache to have it again)