title: Select2 open dropdown on focus text input
body: <p>I have a form with one text input and one select2 element (Version 4.0.0). I want when focus on text input, the select2 open.</p>
  
  <p>Here’s what I’ve tried :</p>
  
  <pre><code>&lt;select list="userAccountsMap.values" listKey="accountNo" listValue="accountNo"/&gt;
  &lt;input id="destinationAccount" type="text" name="destinationAccount"&gt;
  
  &lt;script type="text/javascript"&gt;
  
  ('select').each(function( index ) {
           $(this).select2();
       }
  });
  
  $("#destinationAccount").focus(function () {    
     $("select").trigger('select2:open');
  });
  
  &lt;/script&gt;
  </code></pre>
  
  <p>But it is not work. 
  See fiddle here: <a href="http://jsfiddle.net/Hatamikhah/73wypp1w/1/" rel="nofollow">http://jsfiddle.net/Hatamikhah/73wypp1w/1/</a></p>
  
  <p>I don't understand what my problem is.</p>