title: Why user agent change in IE9 with browser mode IE9 <F12 developer tools>?
body: <p>The code is </p>
  
  <pre><code>&lt;html&gt;
  &lt;body&gt;
  &lt;script type="text/javascript"&gt;
      document.write("&lt;p&gt;UserAgent: ")
      document.write(navigator.userAgent + "&lt;/p&gt;")
  &lt;/script&gt;
  &lt;/body&gt;
  &lt;/html&gt; 
  </code></pre>
  
  <p>Save it as html file and open it in IE9. You will see FULL user agent is shown.</p>
  
  <p>But, if you press F12 to open developer tools, then re-select browser mode as 'IE9' (even current browser mode is IE9), SHORT user agent is shown.</p>
  
  <p>Why?</p>
  
  <p>Big Thanks!</p>