<!-- This Source Code Form is subject to the terms of the Mozilla Public
- License, v. 2.0. If a copy of the MPL was not distributed with this
- file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
<html>
<body>
<button id=post>post!</button>
</body>
<script>
window.addEventListener("message", event => {
console.log("Document message", event, event.data, event.source !== window && event.source === window.parent);
});
window.addEventListener("click", event => {
if (event.target.id === "post") {
console.log("click!")
window.parent.postMessage("ping!", "*");
}
});
console.log(window.parent === window)
</script>
</html>