Only come across this post and know I missed step 1 for my mac VPN after 5 days of searching/testing

MacOS/IOS development is insane. There are so many hidden process that are not documented anywhere.

A similar question is asked here a year ago: https://developer.apple.com/forums/thread/116685 I'm assuming the answer is in the MacOS.entitlement file, add the suffix of -systemextension. Is this correct?

It's actually a bit different. After decoding, mine does have networkextension in the config. However the xcode still showing doesn't match the entitlements file's value for the com.apple.developer.networking.networkextension entitlement. dict keycom.apple.developer.networking.networkextension/key array stringpacket-tunnel-provider-systemextension/string stringapp-proxy-provider-systemextension/string stringcontent-filter-provider-systemextension/string stringdns-proxy-systemextension/string stringdns-settings/string /array keycom.apple.application-identifier/key string*/string keykeychain-access-groups/key array string*/string /array keycom.apple.developer.team-identifier/key string*/string /dict

I have exactly the same issue here. If I generate a distribution/developer profile, it works perfectly fine. However if I generate a developerID profile, it just shows missing that network extension error.