I am performing some tests that involves the app extension and an external app connected through XPC I get the following when I try to connect to an external app from the safari app extension with sandbox enabled connection to service named "com.test.sample"was invalidated: failed at lookup with error 159 - Sandbox restriction." UserInfo={NSDebugDescription=The connection to service named com.test.sample was invalidated: failed at lookup with error 159 - Sandbox restriction. I have tried: Disabling the sandbox for the app extension target Adding the entitlements file path in the test target Both of which still give me the same result. How can I proceed with this? Does the entitlement for the sandbox only work when Safari is running the appex?