Both in VERTO and in SIP.js flavor, the WebRTC Rooms application script is very similar. Actually, VERTO flavor was the one written first, as a companion to the "Mastering FreeSWITCH" Packt book published on occasion of ClueCon 2016. In that book you can read an almost line by line discussion of it. This new version has some fixes and added features (automatic answer to incoming calls, better management of DTMF sending during a call, possibility to call non numeric extensions, and various polish).
$(window).load(function() { cur_call = null; chatting_with = false; $("#conference").show(); $("#ext").hide(); $("#backbtn").hide(); $("#cidname").hide(); $("#callbtn").hide(); $("#hupbtn").hide(); $("#chatwin").hide(); $("#chatmsg").hide(); ...