diff --git a/package-lock.json b/package-lock.json
index 99202fdd..73b7c2a1 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -102,7 +102,7 @@
         "sinon": "21.0.0",
         "typescript": "5.8.3",
         "typescript-eslint": "^8.38.0",
-        "webidl2": "24.4.1",
+        "webidl2": "24.5.0",
         "yaml": "2.8.0"
       },
       "engines": {
@@ -17152,13 +17152,13 @@
       "license": "BSD-2-Clause"
     },
     "node_modules/webidl2": {
-      "version": "24.4.1",
-      "resolved": "https://registry.npmjs.org/webidl2/-/webidl2-24.4.1.tgz",
-      "integrity": "sha512-cPToqvZlxTAlaMucZyU28XtFLJz3XPdTdIWK/r3IaP1jfkjqne3OTniJS8DZqfzee1aBUQn80d6s2vYert50kg==",
+      "version": "24.5.0",
+      "resolved": "https://registry.npmjs.org/webidl2/-/webidl2-24.5.0.tgz",
+      "integrity": "sha512-fxOigKkIem1iAgQ9t4cFOP+kWEA8y6Be/uh50FpJh0FijoeeT/VMrOyJzNLUgjy0rGMEcHeReKDCqj0g9dIe9A==",
       "dev": true,
       "license": "W3C",
       "engines": {
-        "node": ">= 14"
+        "node": ">= 18"
       }
     },
     "node_modules/whatwg-encoding": {
diff --git a/package.json b/package.json
index bb3d4528..93ed21fd 100644
--- a/package.json
+++ b/package.json
@@ -136,7 +136,7 @@
     "sinon": "21.0.0",
     "typescript": "5.8.3",
     "typescript-eslint": "^8.38.0",
-    "webidl2": "24.4.1",
+    "webidl2": "24.5.0",
     "yaml": "2.8.0"
   }
 }
diff --git a/test-builder/api.test.ts b/test-builder/api.test.ts
index 5546d69e..453ed54e 100644
--- a/test-builder/api.test.ts
+++ b/test-builder/api.test.ts
@@ -660,7 +660,7 @@ describe("build (API)", () => {
       const ast = WebIDL2.parse(
         `[Exposed=Window]
            interface ReadableStream {
-             async iterable<any>;
+             async_iterable<any>;
            };`,
       );
       assert.deepEqual(await buildIDLTests(ast, [], scopes), {
@@ -683,7 +683,7 @@ describe("build (API)", () => {
       const ast = WebIDL2.parse(
         `[Exposed=Window]
            interface AsyncMap {
-             async iterable<DOMString, any>;
+             async_iterable<DOMString, any>;
            };`,
       );
       assert.deepEqual(await buildIDLTests(ast, [], scopes), {
diff --git a/test-builder/api.ts b/test-builder/api.ts
index 868c0c5b..442e3673 100644
--- a/test-builder/api.ts
+++ b/test-builder/api.ts
@@ -213,7 +213,8 @@ const flattenMembers = (iface) => {
         members.push({name: iface.name, type: "constructor"});
         break;
       case "iterable":
-        if (member.async) {
+      case "async_iterable":
+        if (member.async || member.type === "async_iterable") {
           // https://webidl.spec.whatwg.org/#idl-async-iterable
           members.push(
             {name: "@@asyncIterator", type: "symbol"},
@@ -404,10 +405,13 @@ const getExposureSet = (node, scopes): Set<Exposure> => {
 const validateIDL = (ast) => {
   const validations = WebIDL2.validate(ast).filter((v) => {
     // Ignore the [LegacyNoInterfaceObject] rule.
-    // XXX Also temporarily ignore the "[AllowShared] BufferSource -> AllowSharedBufferSource" rule until specs are fixed.
-    return !["no-nointerfaceobject", "migrate-allowshared"].includes(
-      v.ruleName,
-    );
+    // Also ignore the "async iterable -> async_iterable" rule until specs are fixed.
+    // Also ignore the rule that dictionary arguments without required fields must be marked optional (until the RTC spec is fixed)
+    return ![
+      "no-nointerfaceobject",
+      "obsolete-async-iterable-syntax",
+      "dict-arg-optional",
+    ].includes(v.ruleName);
   });
   if (validations.length) {
     const message = validations