title: How to create a dropdown list with predefined values but there should also be the option to add a new one to the list
body: <p>I want to create a dropdown list with predefined values but there should also be an option to add a new one to the list.</p>
  
  <pre><code>    &lt;select name="" id="input" class="form-control" required="required"&gt;
      &lt;option value="1"&gt;1&lt;/option&gt;
      &lt;option value="2"&gt;2&lt;/option&gt;
      &lt;option value="3"&gt;3&lt;/option&gt;
      &lt;option value=""&gt;Enter new value&lt;/option&gt;
      &lt;/select&gt;
  </code></pre>
  
  <p>In the above code I want an option to add new <code>&lt;option&gt;</code> tag, with which I could add a new value to the list and post to the server.</p>