I was confused by this too. It said 'Or Login With Facebook' but when I clicked that it only turned into 'Facebook connected' and I still had to enter an email

I was confused by this too. It said 'Or Login With Facebook' but when I clicked that it only turned into 'Facebook connected' and I still had to enter an email and password. That was confusing and I considered stopping. I went through with it anyway, but that part was strange. Why do you do that?