How to get local IP address via JavaScript

myIP.js

// found at https://stackoverflow.com/a/32841043
// many thanks to author!
window.RTCPeerConnection = window.RTCPeerConnection || window.mozRTCPeerConnection || window.webkitRTCPeerConnection;
// Firefox & Chrome only! This will not work in Edge!
    
var pc = new RTCPeerConnection({iceServers:[]}), noop = function(){};      
pc.createDataChannel('');//create a bogus data channel
pc.createOffer(pc.setLocalDescription.bind(pc), noop);// create offer and set local description
pc.onicecandidate = function(ice) {
    if (ice && ice.candidate && ice.candidate.candidate) {
        var myIP = /([0-9]{1,3}(\.[0-9]{1,3}){3}|[a-f0-9]{1,4}(:[a-f0-9]{1,4}){7})/.exec(ice.candidate.candidate)[1];
        $('#showIP').append('Current IP : '+ myIP);
        pc.onicecandidate = noop;
    }
};