Comment 81 for bug 339772

I really disagree with this feature request, for 2 reasons. First, Firefox is
meant to be small and efficient, leaving most unnecessary features to extensions
and plugins. Adding bittorrent would not help normal users who never use BT, and
would not help power users since the implementation would most likely be very
basic and the power users would continue to use 3rd party programs anyways.

Second reason, BT is a very problematic protocol. It's hell with firewalls and
routers, because it needs both upload and download, at large port ranges,
leading to tons of user complaints about problems. Also most ISPs have bandwidth
limits, meaning many people decide not to use BT. Having it built in Firefox,
especially as the reporter suggest (being hidden and continue to upload past
100% without user consent) is a terrible terrible idea.

So no thanks, tons of bugs to work on anyways.