I attempted to set up a laptop for my daughter before Xmas with my own admin account and hers as a managed account with parental controls on. We fire it up on Xmas morning and it's forgotten almost everything I set up - in particular the whitelisted apps. I switch to my user, set it all up again, switch back, it's forgotten again. Did some googling and it turns out this bug has been around for at least two years [1][2]. This seems like absolutely fundamental functionality, there are effectively no parental controls as it's unable to remember any of the settings.

[1] https://discussions.apple.com/thread/7275030 [2] https://apple.stackexchange.com/questions/220067/cannot-save...