6.1. Configuring Firefox to Use Kerberos for Single Sign-On
Firefox can use Kerberos for single sign-on to intranet sites and other protected websites. For Firefox to use Kerberos, it first has to be configured to send Kerberos credentials to the appropriate KDC.
If Kerberos authentication is not working, turn on verbose logging for the authentication process.
There are several common errors that occur with Kerberos authentication.