details.js

/**
 * @file
 * Additional functionality for HTML5 details elements.
 */

(function ($) {
  /**
   * Open parent details elements of a targeted page fragment.
   *
   * Opens all (nested) details element on a hash change or fragment link click
   * when the target is a child element, in order to make sure the targeted
   * element is visible. Aria attributes on the summary
   * are set by triggering the click event listener in details-aria.js.
   *
   * @param {jQuery.Event} e
   *   The event triggered.
   * @param {jQuery} $target
   *   The targeted node as a jQuery object.
   */
  const handleFragmentLinkClickOrHashChange = (e, $target) => {
    $target.parents('details').not('[open]').find('> summary').trigger('click');
  };

  /**
   * Binds a listener to handle fragment link clicks and URL hash changes.
   */
  $('body').on(
    'formFragmentLinkClickOrHashChange.details',
    handleFragmentLinkClickOrHashChange,
  );
})(jQuery);