text: 
  var myImage = document.querySelector('img');
  
  myImage.onclick = function(){
      var mySrc = myImage.getAttribute('src');
  
      if(mySrc === 'images/firefox-icon.png'){
          myImage.setAttribute('src', 'images/firefox-icon2.png');
      }else{
          myImage.setAttribute('src', 'images/firefox-icon.png');
      }
  } 
  
  var myButton = document.querySelector('button');
  var myTitle = document.querySelector('h1');
  
  if(!localStorage.getItem('nombre')){
      setNameUser();
  }else{
      var storeName = localStorage.getItem('nombre');
      myTitle.textContent = 'Mozilla es fresco, ' + storeName;
  }
  
  function setNameUser(){
      var myName = prompt('Por favor, ingrese tu nombre.');
      localStorage.setItem('nombre', myName);
      myTitle.textContent = 'Mozilla es fresco, ' + myName;
  
  }
  
  myButton.onclick = function(){
      setNameUser();
  }