bellbind/index.html

## index.html
<!doctype html>
<html>
  <head>
    <script type="module">
const worker = new SharedWorker("./worker.js");
worker.port.addEventListener("message", ev => {
  document.body.textContent = `connected: ${ev.data}`;
});
worker.port.start(); // spawm connect event to a shared worker
    </script>
  </head>
  <body></body>
</html>

## worker.js
// shared state for each script url
// - reset after all page closed (all ServiceWorker instance terminated)
let counter = 0;

this.addEventListener("connect", ev => {
  counter++;
  const port = ev.ports[0]; // port of each ServiceWorker instances
  port.postMessage(counter);
});
	<!doctype html>
	<html>
	<head>
	<script type="module">
	const worker = new SharedWorker("./worker.js");
	worker.port.addEventListener("message", ev => {
	document.body.textContent = `connected: ${ev.data}`;
	});
	worker.port.start(); // spawm connect event to a shared worker
	</script>
	</head>
	<body></body>
	</html>
	// shared state for each script url
	// - reset after all page closed (all ServiceWorker instance terminated)
	let counter = 0;

	this.addEventListener("connect", ev => {
	counter++;
	const port = ev.ports[0]; // port of each ServiceWorker instances
	port.postMessage(counter);
	});