https://pays-epernay.fr/modules/contrib/field_group/js/field_group.tab_validation.js?t29xam

1(function ($, once) {
2  /**
3   * Invalid event handler for input elements in Tab field group.
4   */
5  const onTabInvalid = function (e) {
6    $(e.target)
7      .parents('details ')
8      .children(
9        'summary[aria-expanded=false]:not(.horizontal-tabs-pane > summary, .vertical-tabs__pane > summary)',
10      )
11      .parent()
12      .attr('open', 'open');
13  };
14
15  /**
16   * Make sure tab field groups which contain invalid data are expanded when
17   * they first load, and also when someone clicks the submit button.
18   */
19  Drupal.behaviors.fieldGroupTabValidation = {
20    attach(context) {
21      $(
22        once(
23          'field-group-tab-validation',
24          $('.field-group-tab :input', context),
25        ),
26      ).on('invalid.field_group', onTabInvalid);
27    },
28  };
29})(jQuery, once);