So far so good, it does what it says. But I'm not going to use it. What I'd like to see:
1. Create a session without closing the current window.
2. The ability to associate a window to a session with live tracking. So I can create a "news" session containing all the tabs of the current window, if I navigate in a tab or I open or close a tab the session is updated. I can now close the window at any time and later restore my "news" window and find all my tabs as they where when I closed the window. This way I can create different sessions/windows like "work", "social media", "sports", "news" and so on.