title: Search box not showing post list
body: <p>I'm hoping you can help me with an issue that I can't solve.
  When I updated <code>wordpress</code> to the latest version, <code>select2</code> lost the functionality to show the latest posts.</p>
  
  <p><a href="https://i.stack.imgur.com/fJzOS.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/fJzOS.png" alt="enter image description here"></a></p>
  
  <p>The above image is the example of what is happening. Instead it should <strong>search and show a list of the last posts by default</strong>, without the need to write anything.</p>
  
  <p>The <code>javascript</code> code that we built to circumvent the situation should correct this behaviour, but the trigger is not working properly and only works when a key is pressed inside the box.</p>
  
  <p><strong>Question:</strong> Has anyone ever had this problem?</p>
  
  <pre><code>$(document).ready(function () {
  
      var select2_open;
      // open select2 dropdown on focus
      $(document).on('focus', '.select2-selection--single', function (e) {
  
          select2_open = $(this).parent().parent().siblings('select');
          $('.select2-search__field').val(' ');
          // trigger keydown event, currently not working
              $('.select2-search__field').trigger('keyup.search');
  
      });
  
  
  });
  </code></pre>