JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://unpkg.com/react@16/umd/react.development.js"></script>
<script src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"></script>
<script src="https://rawgit.com/eu81273/jsfiddle-console/master/console.js"></script>
<div id="container"></div>

Babel + JSX

function log(){
	const descr = Object.getOwnPropertyDescriptor(window, 'event');
  if (typeof descr === 'undefined'){
  	console.log('undefined');
  }else {
  	console.log(JSON.stringify(descr));
  }
}

console.log('Global `window.event` descriptor before/after dispatching a fake event:');

log();
ReactDOM.render(
	<h1 onClick={(type)=>{console.log(evt.type)}}>React Component</h1>,
  document.getElementById('container')
);
log();