Part of being a test team is keeping our tools up to date. Many of you probably have experience using Litmus, which is our repository of manual test cases. Currently members of the Test Execution team own various subgroups and are responsible for keeping the test cases in that subgroup up to date.  You can see the current list of owned areas here: https://wiki.mozilla.org/QA/Litmus/BFT.
As you can see there are currently some unowned areas (and some new areas possibly coming down the pike as development progresses on the next Firefox release).  Interested in helping own one of these areas?  Please contact marcia@mozilla.org.  We can help you get up to speed and learn the steps necessary to keep our test cases in good order for the community!