A wide range of applications, from video players to backup software, can slow this game down. For best results, hide all other windows on your desktop and close graphics intensive apps when you play HTML5 games.
You should also upgrade your browser to the latest version to 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 to the latest version of Chrome.
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