Recently I tried a script uses Request Animation Frame with jsTimers-rAF-hack on firefox nightly and I saw it doesn’t work. I debugged and I saw requestAnimationFrame into window object, but cancelAnimationFrame doesn’t, so the find browser methods doesn’t work fine.
So this is Erik Möller polyfill find browser methods fixed
var vendors = ['ms', 'moz', 'webkit', 'o']; for(var x = 0; x < vendors.length && (window.requestAnimationFrame===undefined || window.cancelAnimationFrame === undefined); ++x) { if(window.requestAnimationFrame === undefined) window.requestAnimationFrame = window[vendors[x]+'RequestAnimationFrame']; if(window.cancelAnimationFrame === undefined) window.cancelAnimationFrame = window[vendors[x]+'CancelAnimationFrame'] || window[vendors[x]+'CancelRequestAnimationFrame']; } if (!window.requestAnimationFrame) //do some thing