title: screen.width/height give wrong info about screen resolution
body: <p>My screen have resolution 1200 x 800 but this script give me 1429 x 893</p>
  
  <pre><code>&lt;script&gt;
  if (screen) { 
  var str = "Screen width:" + screen.width + "\n" + 
            "Screen height:" +  screen.height;
  alert(str);
  }
  &lt;/script&gt;
  </code></pre>
  
  <p>Why it doesn't work?</p>
  
  <p>p.s. On other site this code <code>screen.width + screen.height</code> but when run it on localhost it give wrong info.</p>