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Hi, I tried to install a simple "Hello, world" SystemExtension I created, however I get the following error:Error Domain=OSSystemExtensionErrorDomain Code=8 "Invalid code signature or missing entitlements" UserInfo={NSLocalizedDescription=Invalid code signature or missing entitlements}When I search this code in the SystemExtensions documentation, code 8 specifically means an there was an invalid code signature. I have signed both the extension and the parent application with a free Apple Developer account identity (with Xcode set to manage signing identities automatically). However, due to the lack of documentation on SystemExtensions, I'm clueless as to what's required for a SystemExtension. I've also tried signing them with local-machine-only identities (i.e. only valid for my system), but this doesn't let them load either. What am I missing here?