JSFiddle - React, Tailwind, and code Playground

HTML

<div id="results">
  empty
</div>
<div id="selectcontainer">
  <select class="myselectthing">
    <option value="me">choose me</option>
    <option value="ralf">choose ralf</option>
    <option value="charlie">choose charlie</option>
  </select>
</div>

JavaScript

$('#selectcontainer').on('change focusin manual keydown', ".myselectthing", function(e) {
  var selectionIndex = $(this).prop('selectedIndex');
  $('#results').text("this type " + e.type + ":" + $(this).val() + " : " + selectionIndex);
});

$('#selectcontainer').find('.myselectthing').val("ralf").trigger("manual");