example.html

<div id="messages"></div>
<form>
	<input type="text" id="message" />
	<input type="submit" />
</form>

<script src="https://wzrd.in/standalone/browser-bus@latest"></script>
<script>
	var bus = window.browserBus({
		relay: 'https://srcagency.github.com/browser-bus/relay.html',
	});

	var $messages = document.querySelector('#messages');
	var $message = document.querySelector('#message');
	var $form = document.querySelector('form');

	$form.addEventListener('submit', function( e ){
		e.preventDefault();

		var message = $message.value;
		$message.value = '';

		bus.write(message);

		add(message);
	});

	bus.listen(add);

	function add( message ){
		var $message = document.createElement('p');
		$message.textContent = message;

		$messages.appendChild($message);
	}
</script>