I'd like to set up 2 factor authentication on Facebook that uses my phone. In Facebook's security settings I've gotten to "Set Up a Third Party App to Generate Codes". It gave me a QR code to scan which I succesfully added to Google Authenticator but when I sign into Facebook it never asks for it and doesn't require it. I also tried Facebook's Code Generator app, but when I click add it doesn't launch any camera app.
How can I have my Facebook account prompt me for a changing password in addition to my regular one?