title: Unstoppable addEventListener
body: <p>When I click on the link it's working perfectly but only ONCE.</p>
  
  <p>I want to be able to be able to keep the <code>addEventListener</code> even after it's been executed.</p>
  
  <pre><code>&lt;div id=myBox&gt;
      &lt;a href="#" id="append"&gt;append&lt;/a&gt;
  &lt;/div&gt;
  </code></pre>
  
  <pre class="lang-js prettyprint-override"><code>document.getElementById("append").addEventListener("click", appendMore);
  function appendMore() {
      myBox.innerHTML += '1';
  }
  </code></pre>