Shows the hosting location, rank and risk rating for all sites that you visit.
Firefox has a special interface for viewing and setting a wide variety of configuration variables, many of which are not otherwise accessible through the GUI (options panels). Below are some of the most useful preferences. If you can't find the preference name below in your own about:config listings, you'll have to create it as a new entry:
These are not supported by all servers and may cause refused connections or other unusual behavior: