https://nationaltrailraceway.com/core/misc/announce.js?v=8.9.11

1/**
2* DO NOT EDIT THIS FILE.
3* See the following change record for more information,
4* https://www.drupal.org/node/2815083
5* @preserve
6**/
7
8(function (Drupal, debounce) {
9  var liveElement = void 0;
10  var announcements = [];
11
12  Drupal.behaviors.drupalAnnounce = {
13    attach: function attach(context) {
14      if (!liveElement) {
15        liveElement = document.createElement('div');
16        liveElement.id = 'drupal-live-announce';
17        liveElement.className = 'visually-hidden';
18        liveElement.setAttribute('aria-live', 'polite');
19        liveElement.setAttribute('aria-busy', 'false');
20        document.body.appendChild(liveElement);
21      }
22    }
23  };
24
25  function announce() {
26    var text = [];
27    var priority = 'polite';
28    var announcement = void 0;
29
30    var il = announcements.length;
31    for (var i = 0; i < il; i++) {
32      announcement = announcements.pop();
33      text.unshift(announcement.text);
34
35      if (announcement.priority === 'assertive') {
36        priority = 'assertive';
37      }
38    }
39
40    if (text.length) {
41      liveElement.innerHTML = '';
42
43      liveElement.setAttribute('aria-busy', 'true');
44
45      liveElement.setAttribute('aria-live', priority);
46
47      liveElement.innerHTML = text.join('\n');
48
49      liveElement.setAttribute('aria-busy', 'false');
50    }
51  }
52
53  Drupal.announce = function (text, priority) {
54    announcements.push({
55      text: text,
56      priority: priority
57    });
58
59    return debounce(announce, 200)();
60  };
61})(Drupal, Drupal.debounce);