text: //Funcion para mostrar un elemento
  function mostrarFormulario(id)
  {
    var inbox=document.getElementById('inboxform');
    var compose=document.getElementById('composeform');
  
    if (id == 'inboxform'){
      inbox.style.display="block";
      compose.style.display="none";
    }else{
      inbox.style.display="none";
      compose.style.display="block";
    }
  }
  
  function mostrarurl(url){
    alert('prueba');
    $("#boton").click(function(event) {
      $("#htmlext").load(url);
    });
  
  }
  