fix(core,web): honour flutterfire_ignore_scripts under dart2wasm

packages/firebase_core/firebase_core_web/lib/src/firebase_core_web.dart

@@ -117,16 +117,15 @@ class FirebaseCoreWeb extends FirebasePlatform {
   /// You must ensure the Firebase script is injected before using the service.
   List<String> get _ignoredServiceScripts {
     try {
-      JSObject? ignored =
+      final ignored =
           globalContext.getProperty('flutterfire_ignore_scripts'.toJS);
-
-      // Cannot be done with Dart 3.2 constraints
-      // ignore: invalid_runtime_check_with_js_interop_types
-      if (ignored is Iterable) {
-        // ignore: invalid_runtime_check_with_js_interop_types
-        return (ignored! as Iterable)
-            .map((e) => e.toString())
-            .toList(growable: false);
+      if (ignored != null && ignored.isA<JSArray>()) {
+        return (ignored as JSArray<JSAny?>).toDart.map((entry) {
+          if (entry != null && entry.isA<JSString>()) {
+            return (entry as JSString).toDart;
+          }
+          return entry?.toString() ?? 'null';
+        }).toList(growable: false);
       }
     } catch (e) {
       // Noop
@@ -135,6 +134,10 @@ class FirebaseCoreWeb extends FirebasePlatform {
     return [];
   }
 
+  /// Services listed on `window.flutterfire_ignore_scripts`.
+  @visibleForTesting
+  List<String> get ignoredServiceScripts => _ignoredServiceScripts;
+
   final String _defaultTrustedPolicyName = 'flutterfire-';
 
   /// Injects a `script` with a `src` dynamically into the head of the current

packages/firebase_core/firebase_core_web/test/firebase_core_web_ignore_scripts_test.dart

@@ -0,0 +1,41 @@
+// Copyright 2026 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+@TestOn('browser')
+library;
+
+import 'dart:js_interop';
+import 'dart:js_interop_unsafe';
+
+import 'package:firebase_core_web/firebase_core_web.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  tearDown(() {
+    globalContext.delete('flutterfire_ignore_scripts'.toJS);
+  });
+
+  test('reads service names from a JS array on window', () {
+    // Matches `window.flutterfire_ignore_scripts = ['analytics'];` in index.html.
+    globalContext.callMethod(
+      'eval'.toJS,
+      "window.flutterfire_ignore_scripts = ['analytics', 'firestore']".toJS,
+    );
+
+    expect(
+      FirebaseCoreWeb().ignoredServiceScripts,
+      ['analytics', 'firestore'],
+    );
+  });
+
+  test('returns an empty list when the window property is missing', () {
+    expect(FirebaseCoreWeb().ignoredServiceScripts, isEmpty);
+  });
+
+  test('returns an empty list when the window property is not an array', () {
+    globalContext['flutterfire_ignore_scripts'] = 'analytics'.toJS;
+
+    expect(FirebaseCoreWeb().ignoredServiceScripts, isEmpty);
+  });
+}