https://www.darpa.mil/themes/custom/darpa_uswds/assets/js/packages/secondary_menu/secondary_menu.js?tm7so2

1(function (Drupal) {
2  Drupal.behaviors.viewActiveLinks = {
3    attach: function (context, settings) {
4      // Targets links within your view that match the current path
5      const currentPath = window.location.pathname;
6      // This matches Views  block secondary nav version and Paragraph secondary nav version.
7      const viewLinks = context.querySelectorAll('.treas-secondary-nav a[href="' + currentPath + '"]');
8
9      viewLinks.forEach(function (link) {
10        link.classList.add('active'); // or 'is-active' to match Drupal core
11      });
12    }
13  };
14})(Drupal);