https://www.kirkwallbaptistchurch.org.uk/Common/Scripts/media-es6.js

1//Media functions that cause the main script bundle to fail to compile in IE11
2var MediaES6 = (function ($) {
3    "use strict";
4
5    var CacheMediaFile = async function (url, $spinner) {
6        $spinner.show();
7        $spinner.siblings("a.media-file-download").hide();
8        const cache = await caches.open('media');
9        try {
10            await cache.add(url);
11            $spinner.siblings("a.media-file-download").show();
12            $spinner.closest(".media-file").addClass("available-offline");
13            if (typeof window.top.appAudit == "function") {
14                window.top.appAudit(9); //AppMain.AppAuditEvent.MEDIA_ITEM_OFFLINED
15            }
16        }
17        catch (err) {
18            $spinner.siblings("a.media-file-download").show();
19            Insight.Alert("Unable to download file. (" + url + ")");
20        }
21        finally {
22            $spinner.hide();
23        }
24    };
25
26    return {
27        CacheMediaFile: CacheMediaFile
28    };
29}($e));