How to disconnect JavaScript popup from opener

Question

I\'m opening a popup from my main page with code like this:

Answer 1

If the page in the child window is in your control, you can assign null to the opener in the child page:

window.opener = null;

By making this as the first statement in your javascript.

If the page is not in your control or is in a different domain, then do it while opening:

popup = window.open(this.href, '_blank', 'width=512,height=512,left=200,top=100');
popup.opener = null;