title: Disable JavaScript function based on the user's computer's performance
body: <p>My website has a jQuery script (from <em><a href="http://www.bitstorm.org/jquery/shadow-animation/" rel="nofollow noreferrer">Shadow animation jQuery plugin</a></em>) which constantly changes the colour of box shadow of various <code>&lt;div&gt;</code>s on the home page. </p>
  
  <p>The animation is not essential, but it does take up a lot of CPU time on slower machines.</p>
  
  <p>Is it possible to find out if the script will run 'too slowly'? I can then disable it before it impacts performance.</p>
  
  <p>Is this even a good idea? If not, is there an easy way to break up the jQuery animate? </p>