title: Facebook Comments Plugin: disabling "other login providers" doesn't work
body: <p>On the Facebook Comments plugin, under Settings | Other Login Providers, I have unchecked "Allow users to post using other login providers."  However, if I log out of Facebook and land on the page with my plugin, the "comment using..." dropdown still appears.</p>
  
  <p>This seems to be a new behavior -- I didn't notice it last week.  Any workarounds?</p>