macOS parental controls do not allow Roblox

I am trying to get Roblox to work under an account restricted by parental controls. I found this thread:

https://discussions.apple.com/thread/7909226

but no solution was ever found. Roblox support suggests using 3rd-party parental controls, but I don't want to do that.

After trying several things, I got a partial solution.

1. Do not install Roblox as an administrator in /Applications.
2. Set your child's account temporarily as a Standard account.
3. Log in as the child account and install Roblox. It will go in the user's personal Applications folder.
4. Test by playing a Roblox game. It should work. Then log out.
5. Go back to the administrator account and activate Parental controls on the child account. Set up the parental control settings however you want, except that you cannot use the "Limit Applications on this Mac" option. Make sure the settings stick by clicking on the lock on the preferences.
6. Switch to the child account and launch Roblox. Test by playing a Roblox game.
7. If you have "Allow access to only these websites" option in parental controls turned on, you have to allow a lot of sites the first few times you run Roblox. I did eventually get it to work.