Google chrome sessions just wont let go.

We recently discovered that when you enable the "Save tabs" feature in chrome it also saves off the session.

This is an issue if you have a web application that only logs the user out when they close the browser (by localising the cookies and setting expiry to now())

This was a valid technique when you don't want to set a time expiry but you do want the user to be logged out at some point.

But now in practice if I log in close the window and re open it, I'm still logged in.