http://stackoverflow.com/questions/12528049/if-a-dom-element-is-removed-are-its-listeners-also-removed-from-memory

devtools-timeline.gif

leak-memory.html

<script>
function run() {

	function clicked(e) {
		console.log(e);
	}

	for (var i = 0; i < 1000; i++) {
		var span = document.createElement('span');
		span.addEventListener('click', clicked, false);
		document.body.appendChild(span);
	}

	setTimeout(function() {
		var spans = document.querySelectorAll('span');
		for (var i = 0; i < spans.length; i++) {
			var span = spans[i];
			span.parentNode.removeChild(span);
		}
	}, 100);

}
</script>
<button onclick="run()">Run (memory leak)</button>

no-memory-leak.html

<script>
function run() {

	function clicked(e) {
		console.log(e);
	}

	for (var i = 0; i < 1000; i++) {
		var span = document.createElement('span');
		span.addEventListener('click', clicked, false);
		document.body.appendChild(span);
	}

	setTimeout(function() {
		var spans = document.querySelectorAll('span');
		for (var i = 0; i < spans.length; i++) {
			var span = spans[i];
			span.removeEventListener('click', clicked, false); // <-- Fix memory leak
			span.parentNode.removeChild(span);
		}
	}, 100);

}
</script>
<button onclick="run()">Run (no memory leak)</button>