The administrator should be able to view the wiki as another user, or assuming a certain role, to test what that user or role can do.

I think this is important, because WikiJS permissions are not very intuitive when you're trying to achieve a complex permission structure. It's easy to make mistakes.

Ability for admins to hijack users. Enabling the admin to experience the wiki as it would be for the user. This would be helpfull when providing support and testing permissions. This is possible in frameworks like Django through plugins like: https://django-hijack.readthedocs.io/