How is that call to put it on the queue "blocking"? "Blocking" is being used here to describe the UI preventing the user from further interaction (such as readi

How is that call to put it on the queue "blocking"? "Blocking" is being used here to describe the UI preventing the user from further interaction (such as reading a different email) until the server acknowledges receipt. You can still wait for queue acknowledgement without preventing the users from browsing to other parts of the app.