Facebook Code Generator on Windows Phone
If you care about your online security, you would probably enable two factor authentication on every service that supports it. If you enable in facebook you would be prompted to enter a code of your Code Generator application. If you do not know how to obtain such code and ask for helps the site tells you that it is available on your Phone application.
Sadly enough, it seems that Windows Phone Facebook app does not have this option. The simplest solution is using Microsoft Authenticator app, as described in this article.
The algorithm behind secure code generation is a standard, and Microsoft Authenticator Windows Phone app works perfectly even for services that ask you for a Google generator.
Gian Maria.