Hi Eskimo,
Thanks for your reply.
The System Extension contains a Network Content-Filter, so it will not start immediately on activation.
I filed a suggestion FB14606462 for new API/notification when users enable/disable/uninstall System Extension, and I have another reason why such a new API/notification might be helpful. See below for details.
Shay39
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution