--- a/testing/web-platform/meta/MANIFEST.json
+++ b/testing/web-platform/meta/MANIFEST.json
@@ -627513,17 +627513,17 @@
    "76c28a36e4f47f7b01441e74fd4837a2cfd9040d",
    "testharness"
   ],
   "secure-contexts/basic-shared-worker.https.html": [
    "e7c78383a8266bd160dcfc9747b69ebe56530295",
    "testharness"
   ],
   "secure-contexts/idlharness.any.js": [
-   "88341f3b215dd80a164d4144a13ecdf74c1d4ef5",
+   "5bd1d44d6f7d9c299ff41c241802652924ce77b2",
    "testharness"
   ],
   "secure-contexts/postMessage-helper.html": [
    "8971c86b279b3134ee56f74c5414cc3a207e3d41",
    "support"
   ],
   "secure-contexts/postMessage-helper.https.html": [
    "8971c86b279b3134ee56f74c5414cc3a207e3d41",

--- a/testing/web-platform/tests/secure-contexts/idlharness.any.js
+++ b/testing/web-platform/tests/secure-contexts/idlharness.any.js
@@ -1,20 +1,19 @@
 // META: global=window,worker
 // META: script=/resources/WebIDLParser.js
 // META: script=/resources/idlharness.js
 
 // https://w3c.github.io/webappsec-secure-contexts/
 
 'use strict';
 
-promise_test(async () => {
-  const idl = await fetch("/interfaces/secure-contexts.idl").then(r => r.text());
-  const workers = await fetch("/interfaces/dedicated-workers.idl").then(r => r.text());
-
-  const idl_array = new IdlArray();
-  idl_array.add_idls(idl);
-  idl_array.add_dependency_idls(workers);
-  idl_array.add_objects({
-    WindowOrWorkerGlobalScope: ["self"],
-  });
-  idl_array.test();
-}, "Test IDL implementation of Secure Contexts");
+idl_test(
+  ['secure-contexts'],
+  ['html', 'dom'],
+  idl_array => {
+    if (self.Window) {
+      idl_array.add_objects({ Window: ['self'] });
+    } else {
+      idl_array.add_objects({ WorkerGlobalScope: ['self'] });
+    }
+  }
+);