Tryit Editor v2.9

Edit This Code:
<!DOCTYPE html>
<html>
<body>

<p>Click the button to alert the location of the parent window when opening the new window.</p>

<button onclick="myFunction()">Try it</button>

<script>
function myFunction() {
    window.open("", "", "width=200, height=100");
    alert(window.parent.location);
}
</script>

</body>
</html>