title: append / appendChild not working on all items
body: <p>I'm trying to move all the list items from an list to another using only javascript but for some reason only half of them are actually moved.</p>
  
  <p>Heres a working example of what I'm doing:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>var results_ul = document.getElementById('results');
  var stores_li = document.getElementsByClassName('store-list-item');
  
  for (var x = 0; x &lt; stores_li.length; x++) {
    document.getElementById('hide').appendChild(stores_li[x]);
    stores_li[x].className += ' teste';
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;p&gt;results&lt;/p&gt;
  &lt;ul id="results"&gt;
    &lt;li class="store-list-item"&gt;Teste 1&lt;/li&gt;
    &lt;li class="store-list-item"&gt;Teste 2&lt;/li&gt;
    &lt;li class="store-list-item"&gt;Teste 3&lt;/li&gt;
    &lt;li class="store-list-item"&gt;Teste 4&lt;/li&gt;
  &lt;/ul&gt;
  &lt;p&gt;Hide:&lt;/p&gt;
  &lt;ul id="hide"&gt;&lt;/ul&gt;</code></pre>
  </div>
  </div>
  </p>
  
  <p>What seems to be the problem?</p>