What are some alternatives?
When comparing Session Box and Session Buddy, you can also consider the following products
Tabs Outliner - Next Generation Session, Windows, Tabs Manager and a TooManyTabs Solution That Really Works.
OneTab - Whenever you find yourself with too many tabs, click the OneTab icon to convert all of your tabs into a list. When you need to access the tabs again, you can either restore them individually or all at once.
Toby - Better Than Bookmarks
Firefox Multi-account Containers - Sign in to two different accounts on the same site
Multiloginapp - Connect to websites as a multitude of different users
Workona - Workona helps get browser tabs under control to increase productivity and bring focus to its user's work.