title: Why is document.GetElementById returning null
body: <p>I've been using <code>document.GetElementById()</code> successfully but from some time on I can't make it work again.
  look at the following Code:</p>
  <pre class="lang-html prettyprint-override"><code>    &lt;html&gt;
      &lt;head&gt;
       &lt;title&gt;no title&lt;/title&gt; 
       &lt;script type=&quot;text/javascript&quot;&gt;
       document.getElementById(&quot;ThisWillBeNull&quot;).innerHTML = &quot;Why is this null?&quot;;
       &lt;/script&gt;
      &lt;/head&gt;
      &lt;body&gt;
       &lt;div id=&quot;ThisWillBeNull&quot;&gt;&lt;/div&gt;
      &lt;/body&gt;
      &lt;/html&gt;
  </code></pre>
  <p>I am getting <code>document.getElementById(&quot;parsedOutput&quot;) is null</code> all the time now.
  It doesn't matter if I use Firefox or Chrome, or which extensions I have enabled, or what headers I use for the HTML, it's always <code>null</code> and I can't find what could be wrong.</p>