title: Javascript availheight is larger than browser window
body: <p>When I set the height of an element to </p>
  
  <pre><code>screen.availHeight;
  </code></pre>
  
  <p>about 85px of content is cutoff at the bottom in Chrom and about 40px is cutoff from the bottom in IE and ff.  The cutoff content is under the windows taskbar.</p>
  
  <p>how can I fix this</p>