Works fine with other sites like Twitter. Firefox don't even ask to save the FB password?! Instead what happens is FB offers to set up One Tap login! Note that I have not any FB account stored or a FB app installed on the phone, I only use FB with a browser. I tested this with a bare bones install, no add-ons and cleared cache. I am on a Samsung Galaxy S5 with Ice Cream Sandwich 4.4. Any hints very much appreciated.