Remember me functionality is not working

[WishCow]

Having the following line in app/config/security.yml:

firewalls:
    my_area:
        fos_facebook:
            ...
            remember_me: true
            ...

I would expect a REMEMBERME cookie generated on facebook login, but unfortunately this does not happen. Is there some other way to keep the user logged in, after they have logged in facebook?