Will the data be sent when the offline event is triggered to the server?

Question

JavaScript

Good day, there is a task to send a notification to the server after the user logs out of the network.
Suppose an event hangs on the user side:

window.addEventListener("offline", function() {
    //some ajax request
});

As I understand it, the event is triggered when the user's Internet is disconnected, but how in this case will the request reach the server if the Internet is already disconnected?

Answer 1

No way. Listen to the event online and send it there.

Answer 2

This task is solved by maintaining a connection with the client and constant ping, for example, via a websocket. If the user is already offline, obviously nothing will go anywhere.