<!DOCTYPE HTML>
<html>
<body>
<input id="test-input" type="text" value="Yolo"/>
<script type="application/javascript;version=1.7">
  let input = document.getElementById('test-input');
  input.focus();
  
  input.addEventListener('keydown', function(e) {
    e.preventDefault();
  });
</script>
</body>
</html>