Basically What the title says - Is Firefox “Total Cookie Protection” same as Sandboxing individual tabs, e.g. can I do two different logins to the same site in two tabs? Does it work the same way as Multi Account Containers? Thanks in advance!
Edit: updated the post title.
This is not correct. TCP is not a cookie-deletion technique. It keeps all the cookies, it just separates third-party cookies by first-party context.
If you want cookies to be deleted upon closing tabs, try the (excellent) Cookie Auto Delete addon. Be aware that you need to set up exceptions if you don’t want to be logged out of certain sites all the time.