We are experiencing the exact same issue and have also reached out to Apple Support but are still waiting for a response. Have you had any luck resolving this issue, or have you received any updates from Apple? Any insights or advice would be greatly appreciated, thank you!

I was able to read the headers by doing the following: connection.stateUpdateHandler = { newState in switch newState { case .ready: if let metadata = connection.metadata(definition: NWProtocolWebSocket.definition) as? NWProtocolWebSocket.Metadata, let additionalServerHeaders = metadata.additionalServerHeaders { } } } Hope this helps