chromium/third_party/blink/web_tests/external/wpt/wasm/serialization/module/resources/broadcastchannel-iframe.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>A test page that uses a given WebAssembly.Module sent from a BroadcastChannel</title>

<script>
"use strict";
const channel = new BroadcastChannel("channel name");

channel.onmessage = ({ data: { module, i }, source }) => {
  if (!module) {
    // We only care about "broadcasts" from the window
    return;
  }

  let instance = new WebAssembly.Instance(module);
  let increment = instance.exports["increment"];
  let result = increment(i);
  channel.postMessage({i, result});
};
</script>