title: How to capture scroll event on Select2 dropdown?
body: <p>How to capture the <code>scroll</code> event for HTML element that using <code>Select2</code>? 
  I want to capture the scroll event for dynamically adding <code>&lt;option&gt;</code> into my dropdown.</p>
  
  <p><strong>For your infomation:</strong></p>
  
  <ul>
  <li>I'm using <code>jQuery</code>, and the dropdown using <code>Select2</code>.</li>
  <li>The <code>id</code> that of my HTML element is <code>d</code>. (Although the naming isn't appropriate, will rename it later)</li>
  </ul>
  
  <p><strong>Testing solution 1: (Not working)</strong></p>
  
  <pre><code>$("body").on("scroll", "#select2-d-results", function(){
     alert('scroll');
  })
  </code></pre>
  
  <p><strong>Testing solution 2: (Not working)</strong></p>
  
  <pre><code>$('#select2-d-results').scroll(function() {
     alert('scroll');
  });
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/k5Shn.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/k5Shn.png" alt="My Dropdown Selections"></a></p>
  
  <p><a href="https://i.stack.imgur.com/WJAFc.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/WJAFc.png" alt="enter image description here"></a></p>