Firefox Developer Edition 51.0a2 won't work with apache auth ldap (v2.2.14, and v2.4.7). Any intranet resource that uses this authentication method will display a 401 in Firefox right away and work fine in other browsers (the standard auth dialog would pop-up).

I have tried fiddling with about:config settings and clearing my cache with no luck. Can this be fixed or has this feature be turned off in the 51 release?