https://stereolux.org/modules/contrib/webform/js/webform.element.select.js?tl3ix3

1/**
2 * @file
3 * JavaScript behaviors for select menu.
4 */
5
6(function ($, Drupal, once) {
7  /**
8   * Disable select menu options using JavaScript.
9   *
10   * @type {Drupal~behavior}
11   */
12  Drupal.behaviors.webformSelectOptionsDisabled = {
13    attach(context) {
14      $(once('webform-select-options-disabled', 'select[data-webform-select-options-disabled]', context)).each(function () {
15        var $select = $(this);
16        var disabled = $select.attr('data-webform-select-options-disabled').split(/\s*,\s*/);
17        $select.find('option').filter(function isDisabled() {
18          return ($.inArray(this.value, disabled) !== -1);
19        }).attr('disabled', 'disabled');
20      });
21    }
22  };
23
24})(jQuery, Drupal, once);