Whatsapp online tracking

Simple devtools script to track when User is coming online/offline with privacy options on (whatsapp is not showing last seen)

function getElementByXpath(path) {
   return document.evaluate(path, document, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue;
 }
 var online = false;
 setInterval(function() {
  if (getElementByXpath('//*[@id="main"]/header/div[2]/div[1]/div/span').textContent == "User to track") {   var lastSeen = getElementByXpath('//*[@id="main"]/header/div[2]/div[2]/span');
   if (lastSeen != null) {
     var today = new Date();
     var time = today.getHours() + ":" + today.getMinutes() + ":" + today.getSeconds();
     var date = today.getFullYear()+'-'+(today.getMonth()+1)+'-'+today.getDate();
       console.log(date + " "+ time + ", " + lastSeen.textContent);
     if (online == false) {
         new Notification(date + " "+ time + ", " + lastSeen.textContent);
         online = true;
     }
   } else {
      if (online == true) {
         var today = new Date();
         var time = today.getHours() + ":" + today.getMinutes() + ":" + today.getSeconds();
         var date = today.getFullYear()+'-'+(today.getMonth()+1)+'-'+today.getDate();
         new Notification(date + " "+ time + " Offline");
         online = false;
     }
   }
  }
 }, 1000);