One of the exciting new features of Firefox.next is Electrolysis, a project to use multiple processes for different parts of the browser.  Moving to a multi-process model will provide Firefox users with better stability and performance.

There will be many testing challenges involved in the move to a multi-process architecture, but one of the most immediate relates to docshell.  The docshell object is responsible for loading of content from a uri, and managing session and global history objects, among other things.  In Phase II of Eletrolysis, docshell will be hooked up to the multi-process code, so we'd like to have a full suite of docshell tests available to catch any regressions.

I've recently created a docshell sub-harness for Chrome Mochitests that makes writing docshell tests a little easier.  We need to scan the list of fixed docshell bugs and write tests for those that lack them, using this sub-harness as appropriate.  Even if you've never written mochitests before, this is a good project to help with, as I'll be available via irc to help as much as needed.  All that's required is a working knowledge of javascript, and an ability (or a willingness to learn how) to make debug builds and run mochitests.

If you're interested in joining in, you can scan the list of docshell bugs and pick one that you clearly understand, and start writing.  You can review existing docshell tests under mozilla/docshell/test/chrome for examples and inspiration (for example: bug303267), you can peruse information on developing and running mochitests, and you can ping jgriffin on #qa on irc.mozilla.org for help  anytime.