From a code maintainance point of view, how do you manage to keep this 'branch' in track with the main one ? I mean, every patch made to the real firefox has to be carefully reviewed and backported to this multiprocess branch. Is that a manual process ? Or can it be automated like that :

1) Check if new commit arrived on 'head' 2) Auto backport it to the multiprocess branch 3) Try a build + run tests. Everything looks good ? Keep it 4) Not goot ? Send an email to the multiprocess maintainer so that he has a look ?

Is there another way to do that ?