Fixing HTML5 games in Firefox.

I've already tried updating and disabling add ons, so please don't suggest either.
I am developing a series of simple HTML5 games. They work great in Chrome and IE (don't know about Opera, could someone educate me?). However, Firefox runs them slow and jittery.
Example game: http://www.battlegame.net/games/runkitty
What can I do, if anything, to speed up the games in firefox?

See original post by xtmx