Please add option to replace current session with saved session

[Ogden]

I'm not sure how to explain this more.

But basically, all current windows end up getting closed and then the windows and tabs from the saved session get opened

I guess you kinda can do it with "Register for startup"  But that is super annoying.

This really is something TSM has needed for years.  

If the only way to do it is to register the session for startup then restart Firefox then so be it.  It would just be nice to have a button within the TSM popup to do it all at once.

Better yet if it also automatically asked to save the current session.

Please please make this happen, opening saved sessions as it stands is such a pain!