I didn't get any replies on my other question, so I thought I'd reword it. I really like the ability to restict a node to certain members or member groups. However, I have some utilities on the front-end side, that I'd like to also give access to a logged in backoffice user. I don't want to have a Backoffice user to have to create a second Member type account. I had a working "ValidateBackofficeUser()" script, that would determine if they were a Backoffice user, and then used the PerformLogin(userId) to log them in. However, this doesn't appear to be avilalbe in Umbraco 12.0.1. I feel like I've exhaustively searched and can only find a rudimentary way to determine if logged in, but not do a validate and login (as Backoffice User).

Untested, but I think this could be helpful for your problem https://our.umbraco.com/forum/umbraco-9/106857-how-do-i-determine-if-a-backoffice-user-is-logged-in-from-a-razor-view