High-performance applications, such as video players or software that backs up your computer, can slow this game down. For best results, hide all other windows on your desktop and close CPU- or GPU- intensive apps when you play HTML5 games.
You should also upgrade your browser to the latest version and make sure that it has hardware accelerated HTML5 Canvas. Any version of Chrome starting with version 18, for example, has hardware accelerated Canvas. Here is a link where you can download the latest version of Chrome.
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