<!DOCTYPE html>
<html>
<body>
<p>Click the button to write some text in the new window and the source (parent) window.</p>
<button onclick="myFunction()">Try it</button>
<script>
function myFunction() {
var myWindow = window.open("", "myWindow", "width=200,height=100");
myWindow.document.write("<p>This is 'myWindow'</p>");
myWindow.opener.document.write("<p>This is the source window!</p>");
}
</script>
</body>
</html>