Group imessage send causes app to exit (didResignActive) only the first time.

Maybe you have a var not yet initialized when you create first group…

But you don't show enough code to allow proper analysis.

I don't create the group in code. the group is the list of recipients passed in to the app by imessage in the conversation object. The fact that a fresh launch of the application with only a single recipient works fine and a list of recipients fails is telling. Also, a fresh launch of the app in an existing group conversation works fine.

What code would help? I have hundreds of lines of code here. Clean build, no crash in debugger, just jumps to DidResignActive.

I've noticed that if I create a group, then send from the imessage entry a single text (can be just a character), then click on my app in tray it works fine. It's only if you click on the app in the tray w/ out first sending anything else on a group.

I do not fully understand.

then click on my app in tray it works fine. It's only if you click on the app in the tray w/ out first sending anything else on a group. 

Which tray exactly ?

When you open iMessages, click on the compose icon top right. Add two recipients. Then click on the application icon (in this case my app), below the text entry field in the application list tray( same place as the appstore icon and other apps like gif, apple pay, etc.

I was able to create a test app that reproduces this problem, with what I think is the minimal amount of code to demonstrate. Hope this invites a solution!

Code Block ////	MessagesViewController.swift//	testGroupSend MessagesExtension//import UIKitimport Messagesimport osclass MessagesViewController: MSMessagesAppViewController {				override func viewDidLoad() {				super.viewDidLoad()				// Do any additional setup after loading the view.		}				// MARK: - Conversation Handling		func composeSelectionMsg(on conversation: MSConversation, in				session: MSSession) -> MSMessage {				 				let layout = MSMessageTemplateLayout()				layout.caption = "caption..."				let message = MSMessage(session: session)				message.layout = layout				message.summaryText = "summary text..."								var components = URLComponents()				var queryItems = [URLQueryItem]()								queryItems.append(URLQueryItem(name: "MessageType1", value: "msgType"))				queryItems.append(URLQueryItem(name: "Encode-Name", value: "Encode-Value"))				components.queryItems = queryItems				message.url = components.url!								return message		}		func submitMessage() {				guard let conversation = activeConversation else {						os_log("submitMessage(): guard on conversation falied!", log: .default, type: .debug)						return				}				var session : MSSession				if let tSess = conversation.selectedMessage?.session {						session = tSess						os_log("submitMessage() got a session!...", log: .default, type: .debug)				} else {						os_log("###### submitMessage() did NOT get a session, creating new MSSession() #####", log: .default, type: .debug)						session = MSSession()				}				var message: MSMessage				 				message = composeSelectionMsg(on: conversation, in: session)												//	conversation.insert(message) { error in				conversation.send(message) { error in								if let error = error {										os_log("submitMessage(): initial send error: %@", log: .default, type: .debug, error.localizedDescription)								} else {										os_log("submitMessage(): initial send success!", log: .default, type: .debug)								}						}		}		fileprivate func loadContentView() {				os_log("loadContentView()...", log: .default, type: .debug)			 let childViewCtrl = ContentViewHostController()								childViewCtrl.delegate = self				childViewCtrl.view.layoutIfNeeded() // avoids snapshot warning?								if let window = self.view.window {						childViewCtrl.myWindow = window						window.rootViewController = childViewCtrl				}		}				override func willBecomeActive(with conversation: MSConversation) {				loadContentView()		}				override func didResignActive(with conversation: MSConversation) {				os_log("didResignActive()...", log: .default, type: .debug)		}}////import SwiftUIimport Messagesimport osfinal class ContentViewHostController: UIHostingController<ContentView> {		weak var delegate: ContentViewHostControllerDelegate?		weak var myWindow: UIWindow?		init() {								super.init(rootView: ContentView())				rootView.submitMessage = submitMessage		}		required init?(coder: NSCoder) {				super.init(coder: coder, rootView: ContentView())		}		override func viewDidAppear(_ animated: Bool) {				super.viewDidAppear(animated)		}				func submitMessage() {				os_log("ContentViewHostController::submitMessage(): submit message...", log: .default, type: .debug)				delegate?.contentViewHostControllerSubmitMessage(self)		}}struct ContentView: View {		@Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>		var submitMessage: (() -> Void)?			 		var body: some View {				VStack {						VStack {								HStack {										Button(action: { self.cancel() } ) { Image(systemName: "chevron.left") }												.padding()																				Spacer()							 										Button(action: { self.submit() } ) {												Text("Send...")										}										.padding()																		} // HStack						} // VStack				} // outside most VStack		} // body			private func cancel() {				presentationMode.wrappedValue.dismiss()		}				private func submit() {				submitMessage!()				presentationMode.wrappedValue.dismiss()		}} // ContentView////import SwiftUIimport Messagesimport osextension MessagesViewController: ContentViewHostControllerDelegate {				// MARK: - ContenHost delegate				func contentViewHostControllerSubmitMessage(_ controller: ContentViewHostController) {						os_log("delegateSubmitMessage:...")												submitMessage()				}}////import SwiftUIimport Messagesprotocol ContentViewHostControllerDelegate: class	{		func contentViewHostControllerSubmitMessage( _ controller: ContentViewHostController )}

Just to check. Could you introduce a delay in message sending, as described here ?
https://stackoverflow.com/questions/49827017/sending-multiple-messages-in-imessage-using-swift

I modified the above code and tried this... same result...

     DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 2.0, execute: {
      conversation.send(message) { error in
          if let error = error {
            os_log("submitMessage(): initial send error: %@", log: .default, type: .debug, error.localizedDescription)
          } else {
            os_log("submitMessage(): initial send success!", log: .default, type: .debug)
          }
        }
    })

Just an update...
I was told to file a bug report for this (which I did).

I also supplied a video which shows how to reproduce the bug.

This is the message sent back from support...

> Hi,
>
> Thank you contacting Apple Developer Technical Support (DTS).
>
> There is no workaround DTS can provide for Feedback ID #FBxxxxxx; it
> is still under investigation. Please continue to track the problem via
> the bug report.
...