Popsu-coloque/web/core/misc/drupal.init.es6.js

// Allow other JavaScript libraries to use $.
if (window.jQuery) {
  jQuery.noConflict();
}

// Class indicating that JS is enabled; used for styling purpose.
document.documentElement.className += ' js';

// JavaScript should be made compatible with libraries other than jQuery by
// wrapping it in an anonymous closure.
(function(Drupal, drupalSettings) {
  /**
   * Calls callback when document ready.
   *
   * @param {function} callback
   *   The function to be called on document ready.
   */
  const domReady = callback => {
    if (document.readyState !== 'loading') {
      callback();
    } else {
      const listener = () => {
        callback();
        document.removeEventListener('DOMContentLoaded', listener);
      };
      document.addEventListener('DOMContentLoaded', listener);
    }
  };

  // Attach all behaviors.
  domReady(() => {
    Drupal.attachBehaviors(document, drupalSettings);
  });
})(Drupal, window.drupalSettings);