JSFiddle - React, Tailwind, and code Playground

HTML

<button id="btn">Click me!</button>
 
<script>
 
var btn = document.getElementById('btn');
 
btn.onclick = function() { 
  // will be overwritten! 
  console.log('[onclick] foo'); 
}
 
btn.onclick = function() { 
  
  console.log('[onclick] bar');
}
 
btn.addEventListener('click', function() {
  // won't work on IE < 9  
  console.log('[EventListener] foo');
});
 
btn.addEventListener('click', function() {
  // won't work on IE < 9
  console.log('[EventListener] bar');
});
 
</script>