https://beynes.fr/modules/contrib/field_group/js/field_group.tabs_validation.js?tlvj9l

1(function ($, once) {
2  /**
3   * Opens Tab field group with invalid input elements.
4   */
5  const fieldGroupTabsOpen = function ($fieldGroup) {
6    if ($fieldGroup.data('verticalTab')) {
7      $fieldGroup.data('verticalTab').tabShow();
8    } else if ($fieldGroup.data('horizontalTab')) {
9      $fieldGroup.data('horizontalTab').tabShow();
10    } else {
11      $fieldGroup.attr('open', '');
12    }
13  };
14
15  /**
16   * Behaviors for tab validation.
17   */
18  Drupal.behaviors.fieldGroupTabsValidation = {
19    attach(context) {
20      const $inputs = $('.field-group-tabs-wrapper :input', context);
21
22      /**
23       * Invalid event handler for input elements in Tabs field group.
24       */
25      const onTabsInvalid = function (e) {
26        $inputs.off('invalid.field_group', onTabsInvalid);
27        $(e.target)
28          .parents(
29            'details:not(:visible), details.horizontal-tab-hidden, details.vertical-tab-hidden',
30          )
31          .each(function () {
32            fieldGroupTabsOpen($(this));
33          });
34        requestAnimationFrame(function () {
35          $inputs.on('invalid.field_group', onTabsInvalid);
36        });
37      };
38
39      $(once('field-group-tabs-validation', $inputs)).on(
40        'invalid.field_group',
41        onTabsInvalid,
42      );
43    },
44  };
45})(jQuery, once);