Automated User Creation - fill form

fillForm.js

var timestamp = (new Date()).getTime();
var username = 'user-' + timestamp;

var users = localStorage.getItem("users");

if (users) {
  users = users + "," + username;
} else {
  users = username;
}

localStorage.setItem("users", users);

document.getElementById('username').value = username;
document.getElementById('password').value = 'testing123';
document.getElementById('email').value = userName + '@example.com';

document.getElementById('firstName').value = 'Test';
document.getElementById('lastName').value = 'User';

document.getElementById('submitButton').focus();