title: fabricjs: chrome on android is consistently slower than firefox on html5 canvas
body: <p>I have a small web app built on top of fabricjs, with gestures enabled, very similar to the gesture demos on fabricjs tutorial site.</p>
  
  <p>The app draws an image (jpg, 2000x2000) using another image (png, 2500x2500) as a mask.</p>
  
  <p>The web app works flawlessly on desktop PC and in the iPhone; it is slower on Android phones; that's fine, I was expecting this behaviour.</p>
  
  <p>The weird thing is that the same js, on the same device, works much faster under firefox than under chrome.</p>
  
  <p>This behaviour is the same on every android release (tested on android 4.4, 5,x, 6.x) and it's the same on every Android device (tested many, say galaxy note 10.1 2014ed, galaxy note 2, honor 8).</p>
  
  <p>Can you give me any hint? Why chrome, on canvas operations, is consistently slower than firefox?</p>
  
  <p>Thanks!</p>