Cross-domain JavaScript code with sibling sub-domains

Question

I have two web applications setups:

david.example.com and john.example.com

David opens a new window to John:

Answer 1

You should be able to do this, as long as you set document.domain on both DOM's.

document.domain = location.host.replace(/^.*?([^.]+\.[^.]+)$/g,'$1');

Credited to Martin Jespersen