4e4c52/iframe.html

## iframe.html
<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8">
        <title>Iframe</title>
    </head>
    <body>
        <h2>Iframe Content</h2>

        <script>
        // select the iframe node is the parent window
        var target = window.parent.document.querySelector("#iframe");

        // create an observer instance
        var observer = new MutationObserver(function(mutations) {
          mutations.forEach(function(mutation) {
            if (mutation.type == "attributes") {
                if (mutation.target.style.display === "block") {
                    alert("Iframe shown");
                }
                else {
                    alert("Iframe hidden");
                }
            }
          });
        });

        // configuration of the observer:
        var config = { attributes: true, childList: true, characterData: true };

        // pass in the target node, as well as the observer options
        observer.observe(target, config);

        // later, you can stop observing
        // observer.disconnect();

        </script>
    </body>
</html>
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8">
	<title>Iframe</title>
	</head>
	<body>
	<h2>Iframe Content</h2>

	<script>
	// select the iframe node is the parent window
	var target = window.parent.document.querySelector("#iframe");

	// create an observer instance
	var observer = new MutationObserver(function(mutations) {
	mutations.forEach(function(mutation) {
	if (mutation.type == "attributes") {
	if (mutation.target.style.display === "block") {
	alert("Iframe shown");
	}
	else {
	alert("Iframe hidden");
	}
	}
	});
	});

	// configuration of the observer:
	var config = { attributes: true, childList: true, characterData: true };

	// pass in the target node, as well as the observer options
	observer.observe(target, config);

	// later, you can stop observing
	// observer.disconnect();

	</script>
	</body>
	</html>