Hi Quinn! I did some research on that error and I am thinking that the issue is related to how im using/ not using self through out my code. This is how I create my web socket. I am a little confused what i should be using as the delegate and the delegate queue. The class I am working in right now inherits the URLSessionWebSocketDelegate.     let urlString = "ws://localhost:8000"     if let url = URL(string: urlString) {       var request = URLRequest(url: url)       let session = URLSession(configuration: .default, delegate: self, delegateQueue: OperationQueue.main)       webSocket = session.webSocketTask(with: request)       webSocket!.resume()     } Here is my websocket send and receive. I am sending a video stream to a server and I want that stream back to replace the webcam stream. I marked the line in the code bellow that causes the exception in the crash report. The only difference between the testing app that works just fine and the extension that doesn't work is the single if deviceSource._isExtension webSocket?.send(.string(stringData!), completionHandler: { [weak self] error in       guard let weakself = self else {         logger.error("error in setting weak self 1")         return       }       if let error = error {         print("Failed with Error \(error.localizedDescription)")       } else {         weakself.webSocket?.receive(completionHandler: { [weak self] result in           guard let weakself = self else {             logger.error("error in setting weak self 2")             return           }           switch result {           case .failure(let error):             print(error.localizedDescription)           case .success(let message):             switch message {             case .string(let base64Image):                // Processing user input not shown               var timimgInfo = CMSampleTimingInfo()               var formatDescription: CMFormatDescription? = nil               CMVideoFormatDescriptionCreateForImageBuffer(allocator: kCFAllocatorDefault, imageBuffer: pixelBuffer2!, formatDescriptionOut: &formatDescription)               err = CMSampleBufferCreateReadyWithImageBuffer(allocator: kCFAllocatorDefault, imageBuffer: pixelBuffer2!, formatDescription: formatDescription!, sampleTiming: &timimgInfo, sampleBufferOut: &sampleBuffer2)               if err == 0 {                 if deviceSource._isExtension { //Extension code                   if let sb2 = sampleBuffer2 { // this is the line that crashes according to the crash report (ExtensionProvider.swift:400)                     weakself.stream.send(sampleBuffer2!, discontinuity: [], hostTimeInNanoseconds: UInt64(timimgInfo.presentationTimeStamp.seconds * Double(NSEC_PER_SEC)))                   } else {                     logger.error("sb2 is null")                   }                 } else {                   deviceSource.extensionDeviceSourceDelegate?.bufferReceived(sampleBuffer2!) // testing app works just fine                 }               } else {                 logger.error("Error in stream: \(err)")               }             case .data(let data):               let base64Image = String(decoding: data, as: UTF8.self)             default:               print("Unknown type received from WebSocket")             }           }         })       }     })```

crashReport.txt.txt Hi Quinn! Thanks for the response! I commented out the websocket code and I still see the same errors in the Console and the extension runs just fine so I guess we can't attribute my issues to those two messages (though I am still curious about what those messages mean). I have attached the crash report. My primary source of confusion here is why I have no issues with the websockets in my test app and why they cause problems in the system extension. In the app sandbox I have given my extension access to Incoming / Outcoming connections and I see my client (not shown) receiving a few messages before crashing. I have attached the crash report