Login form "Login with Facebook”

There's a few different possibilities. First, try disabling any other extensions that may be trying to communicate with Facebook. If that doesn't help, it's likely a coding error on the page itself. If you have any open tags or other HTML errors that prevent proper parsing of the page, that can easily cause the Javascript to fail or other issues.

If that doesn't help, please let us know what actually happens: no popup, the popup works but you get an error when entering your credentials, page refreshes but doesn't do anything, etc. Also, if you post the URL to your page with the problem, that will help us look to see if there are any common/known configuration problems.

Thanks,
Alex