<!DOCTYPE html>
<html lang="en">
<head>
<!-- ... -->
<script>
function reg() {
window.captureEvents(Event.CLICK);
window.onclick = page_click;
}
function page_click() {
alert('page click event detected!');
}
</script>
</head>
<body onload="reg();">
<p>click anywhere on this page.</p>
</body>
</html>