Xcode 11.4 Unexpected behavior

I updated Xcode to 11.4 today and immediately found unexpectd behavior. Below is a simple view to display all messages in a chat room. When a new message is downloaded from server, the list refreshed automatically to display it. But with Xcode 11.4 and ios 13.4, with a 50:50 chance, a new chat room view will (unexpectly) pop up and all rows behave abnormally. Is there anybody experiencing the same? My code below:


import SwiftUI


struct ChatRoomDetailView: View {

@EnvironmentObject var userData: UserData

@State var messageText: String = ""

@State var isShowingGroupOperation = false

var displayChatRoom: ChatRoom


var thisRoomtitle: String {

if displayChatRoom.isPrivate {

if (displayChatRoom.creatorId == userData.currentUser.name) {return userData.friendNickNames[displayChatRoom.otherUser] ?? displayChatRoom.chatRoomTitle} else {return userData.friendNickNames[displayChatRoom.creatorId] ?? displayChatRoom.chatRoomTitle}

} else {return displayChatRoom.chatRoomTitle}

}


func findIndex(chatRoomId: Int) -> Int {

for (index, value) in userData.chatRooms.enumerated() {

if (value.id == chatRoomId) {return index}

}

return 0

}


var body: some View {

KeyboardHost {

VStack {

List {

ForEach(self.displayChatRoom.messages) {message in

HStack{

if (message.senderId == self.userData.currentUser.name) {

SelfMessageLine(message: message)

} else {OtherMessageLine(message: message)}

}

}

.onDelete {indexSet in

self.userData.deleteMessage(displayChatRoomId: self.displayChatRoom.id, id: self.displayChatRoom.messages[indexSet.sorted()[0]].id)

}

}


......