Locked up FF when I tried it.

Really? I've been using it in FF on GNU/Linux since it was announced 2013-04 without any issue (other than switching to a different tab seems to throttle connections). I've got the latest FF 31. What version/OS/graphics do you have?

Got it.

It was NoScript: NoScript set to allow scripts globally and it works, set to disable scripts by default and it freezes FF.