Whatsapp message Loop

loop_msg.js

// Impress your gf with this simple js
// Open https://web.whatsapp.com/
// select the person you want to send this msg on loop & type the following script on developer console of your browser
var intervalID = setInterval(function () {
var message = document.createEvent("TextEvent");  
message.initTextEvent ("textInput", true, true, window, "I think of you every second", 0, "en-US");
document.getElementsByClassName("input")[1].focus();	// Focus on message box
document.getElementsByClassName("input")[1].dispatchEvent(message); // Type message
document.getElementsByClassName("icon btn-icon icon-send")[0].click(); // Click send
}, 1000); // Repeat every sec

Not working, undefined