my utils

//Load jQuery library using plain JavaScript
(function(){
  var newscript = document.createElement('script');
     newscript.type = 'text/javascript';
     newscript.async = true;
     newscript.src = 'https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js';
  (document.getElementsByTagName('head')[0]||document.getElementsByTagName('body')[0]).appendChild(newscript);
})();

function next_page_or_close(selector){
  next = $(selector);
  if(next.length > 0){
    window.location = next.attr('href')
  }
  else{
    window.close();
  }
}

function sleep(milliseconds) {
  return new Promise(function (resolve, reject) {
    setTimeout(resolve, milliseconds);
  });
}

function asyncForEach(array, func) {
  return new Promise(function (resolve, reject) {
    var i = 0;
    var next = function () {
      i++;
      if (i >= array.length) {
        resolve();
        return;
      }

      func(array[i], i, next);
    };

    func(array[i], i, next);

  });
}

const divs = /* ... */

asyncForEach(divs, (div, index, next) => {
  /* work with div */

  // Wait 1 second
  sleep(1000)
    // Proceed to next div
    .then(next);
});