Ways to detect CTRL-N or when a user opens a new window

Question

How can we detect when a user opens a new window. The user is already authenticated and we make heavy use of sessions.

We were trying to avoid Ctrl+

Answer 1

If opening a new window causes a problem in your application, then you should fix the application code to handle it instead of trying to apply an inconsistent and unreliable client-side "bandage". That's my opinion.