The "new" rfc6265, define max-age attribute as
If a cookie has neither the Max-Age nor the Expires
attribute, the user agent will retain the cookie until "the current session is over" (as defined by the user agent).
Some browsers have the concept of keep the browser session where an user left previous to close the browser (including not deleting session cookies):
Firefox call it:
Restore previous session
Continue where you left off
If a user uses these features, isn't the persistence with "HTTP Cookie Insert" (with session cookie) doomed ?
How to keep an healthy balancing between the nodes if the client always use the same node (because do not delete session cookie)?