title: Javascript insertBefore method cannot be called mulitple times adding same child node?
body: <p>I tried to add same element to the HTML document multiple times, but it doesn't work, I don't know the reason. The code is following: </p>
  
  <pre><code>&lt;html&gt;
  &lt;body&gt;
  
  &lt;div&gt;Very&lt;/div&gt;
  &lt;div&gt;Secret&lt;/div&gt;
  &lt;script&gt;
    var elem = document.createElement('div')
    elem.innerHTML = '**Child**'
  
    document.body.insertBefore(elem,document.body.lastChild);
    document.body.insertBefore(elem,document.body.lastChild);
    document.body.insertBefore(elem,document.body.lastChild);
  &lt;/script&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>why the result is </p>
  
  <pre><code>  Very
    Secret
  **Child**
  </code></pre>
  
  <p>instead of </p>
  
  <pre><code>  Very
    Secret
  **Child**
  **Child**
  **Child**
  </code></pre>