Hi, This is my first post here, happy to join! :-) I'm developing a small runner game, and I'm experiencing different performance problems in different browsers. Any hints, tips, suggestions on how to solve them are very welcome! My unfinished game is here: EDIT: URL REMOVED It runs very smooth on Chrome (I'm using a 2011 MacBookPro). In Firefox, it starts very well after load, but soon it slows down, and sometimes it speeds up again at random (?) places. In Safari it's quite slow from the start. In Mobile Safari (ipad3 and iphone5) I get about the same speed, or even better, compared to Safari on the MacBookPro. I've tried doing browser profiling in Chrome, Firefox and Safari, but I'm kind of confused. It may look like the bottleneck on Firefox is the canvas rendering, but I cant explain the variations in speed over time. And I really can't see why there should be rendering problems at all on a laptop in this case. Any ideas? Best regards, Peter