download_album_in_facebook.js

Array.prototype.slice.call(
  document.querySelectorAll('.fbPhotoStarGridElement')
).filter(function (el) {
  return el.querySelector('.uiMediaThumb');
}).map(function (el) {
  return el.dataset.fbid;
}).forEach(function (id, i) {
  setTimeout(function () {
    var url = 'https://www.facebook.com/photo/download/?fbid=' + id;
    location.href= url;
  }, 1000 * i)}
);