Most of XenForo's update-related features, such as when you see that new posts are available to view when someone posts while you're lurking in a thread, are powered by AJAX. The add-on I linked uses the same AJAX as XenForo at it's core by hooking into it. For those that don't know what Ajax is, please see this: https://www.w3schools.com/js/js_ajax_intro.asp and some JQuery AJAX for advanced stuffs here: https://www.w3schools.com/jquery/jquery_ajax_intro.asp There's even more complicated Shotbox implementations such as https://xenforo.com/community/resources/chat-2-by-siropu.5762/ (by the same author as the previous link I posted). I'll continue to allow feedback in this thread, but generally speaking, I don't believe this will be something that we add to the forum given the cons I listed earlier, unfortunately :(