diff --git a/form_app/pubspec.lock b/form_app/pubspec.lock
index 785abf860..5700e786f 100644
--- a/form_app/pubspec.lock
+++ b/form_app/pubspec.lock
@@ -28,14 +28,14 @@ packages:
       name: async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.5.0-nullsafety.3"
+    version: "2.6.1"
   boolean_selector:
     dependency: transitive
     description:
       name: boolean_selector
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0-nullsafety.3"
+    version: "2.1.0"
   build:
     dependency: transitive
     description:
@@ -98,14 +98,14 @@ packages:
       name: characters
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0-nullsafety.5"
+    version: "1.1.0"
   charcode:
     dependency: transitive
     description:
       name: charcode
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0-nullsafety.3"
+    version: "1.2.0"
   checked_yaml:
     dependency: transitive
     description:
@@ -126,7 +126,7 @@ packages:
       name: clock
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0-nullsafety.3"
+    version: "1.1.0"
   code_builder:
     dependency: transitive
     description:
@@ -140,7 +140,7 @@ packages:
       name: collection
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.15.0-nullsafety.5"
+    version: "1.15.0"
   convert:
     dependency: transitive
     description:
@@ -182,7 +182,7 @@ packages:
       name: fake_async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0-nullsafety.3"
+    version: "1.2.0"
   file:
     dependency: transitive
     description:
@@ -290,14 +290,14 @@ packages:
       name: matcher
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.12.10-nullsafety.3"
+    version: "0.12.10"
   meta:
     dependency: transitive
     description:
       name: meta
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.3.0-nullsafety.6"
+    version: "1.3.0"
   mime:
     dependency: transitive
     description:
@@ -311,7 +311,7 @@ packages:
       name: mockito
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "4.1.1"
+    version: "4.1.1+1"
   node_interop:
     dependency: transitive
     description:
@@ -339,7 +339,7 @@ packages:
       name: path
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0-nullsafety.3"
+    version: "1.8.0"
   pedantic:
     dependency: transitive
     description:
@@ -407,21 +407,21 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0-nullsafety.4"
+    version: "1.8.1"
   stack_trace:
     dependency: transitive
     description:
       name: stack_trace
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.10.0-nullsafety.6"
+    version: "1.10.0"
   stream_channel:
     dependency: transitive
     description:
       name: stream_channel
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0-nullsafety.3"
+    version: "2.1.0"
   stream_transform:
     dependency: transitive
     description:
@@ -435,21 +435,21 @@ packages:
       name: string_scanner
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0-nullsafety.3"
+    version: "1.1.0"
   term_glyph:
     dependency: transitive
     description:
       name: term_glyph
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0-nullsafety.3"
+    version: "1.2.0"
   test_api:
     dependency: transitive
     description:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.19-nullsafety.6"
+    version: "0.3.0"
   timing:
     dependency: transitive
     description:
@@ -463,14 +463,14 @@ packages:
       name: typed_data
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.3.0-nullsafety.5"
+    version: "1.3.0"
   vector_math:
     dependency: transitive
     description:
       name: vector_math
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0-nullsafety.5"
+    version: "2.1.0"
   watcher:
     dependency: transitive
     description:
@@ -493,4 +493,4 @@ packages:
     source: hosted
     version: "2.2.1"
 sdks:
-  dart: ">=2.12.0-0.0 <3.0.0"
+  dart: ">=2.12.0 <3.0.0"
diff --git a/infinite_list/analysis_options.yaml b/infinite_list/analysis_options.yaml
index 30ac27228..85f6fbe91 100644
--- a/infinite_list/analysis_options.yaml
+++ b/infinite_list/analysis_options.yaml
@@ -17,4 +17,3 @@ linter:
     test_types_in_equals: true
     throw_in_finally: true
     unnecessary_statements: true
-    use_key_in_widget_constructors: false
diff --git a/infinite_list/android/app/build.gradle b/infinite_list/android/app/build.gradle
index dfc3ed80e..76d93fc05 100644
--- a/infinite_list/android/app/build.gradle
+++ b/infinite_list/android/app/build.gradle
@@ -26,21 +26,17 @@ apply plugin: 'kotlin-android'
 apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
 
 android {
-    compileSdkVersion 29
+    compileSdkVersion 30
 
     sourceSets {
         main.java.srcDirs += 'src/main/kotlin'
     }
 
-    lintOptions {
-        disable 'InvalidPackage'
-    }
-
     defaultConfig {
         // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
-        applicationId "dev.flutter.infinitelist"
+        applicationId "dev.flutter.infinite_list"
         minSdkVersion 16
-        targetSdkVersion 29
+        targetSdkVersion 30
         versionCode flutterVersionCode.toInteger()
         versionName flutterVersionName
     }
diff --git a/infinite_list/android/app/src/debug/AndroidManifest.xml b/infinite_list/android/app/src/debug/AndroidManifest.xml
index a6f21932c..e82654fa7 100644
--- a/infinite_list/android/app/src/debug/AndroidManifest.xml
+++ b/infinite_list/android/app/src/debug/AndroidManifest.xml
@@ -1,5 +1,5 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="dev.flutter.infinitelist">
+    package="dev.flutter.infinite_list">
     <!-- Flutter needs it to communicate with the running application
          to allow setting breakpoints, to provide hot reload, etc.
     -->
diff --git a/infinite_list/android/app/src/main/AndroidManifest.xml b/infinite_list/android/app/src/main/AndroidManifest.xml
index c0422667d..023668d67 100644
--- a/infinite_list/android/app/src/main/AndroidManifest.xml
+++ b/infinite_list/android/app/src/main/AndroidManifest.xml
@@ -1,13 +1,7 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="dev.flutter.infinitelist">
-    <!-- io.flutter.app.FlutterApplication is an android.app.Application that
-         calls FlutterMain.startInitialization(this); in its onCreate method.
-         In most cases you can leave this as-is, but you if you want to provide
-         additional functionality it is fine to subclass or reimplement
-         FlutterApplication and put your custom class here. -->
-    <application
-        android:name="io.flutter.app.FlutterApplication"
-        android:label="infinitelist"
+    package="dev.flutter.infinite_list">
+   <application
+        android:label="infinite_list"
         android:icon="@mipmap/ic_launcher">
         <activity
             android:name=".MainActivity"
diff --git a/infinite_list/android/app/src/main/kotlin/dev/flutter/infinitelist/MainActivity.kt b/infinite_list/android/app/src/main/kotlin/dev/flutter/infinite_list/MainActivity.kt
similarity index 73%
rename from infinite_list/android/app/src/main/kotlin/dev/flutter/infinitelist/MainActivity.kt
rename to infinite_list/android/app/src/main/kotlin/dev/flutter/infinite_list/MainActivity.kt
index be98af2b6..6b2486135 100644
--- a/infinite_list/android/app/src/main/kotlin/dev/flutter/infinitelist/MainActivity.kt
+++ b/infinite_list/android/app/src/main/kotlin/dev/flutter/infinite_list/MainActivity.kt
@@ -1,4 +1,4 @@
-package dev.flutter.infinitelist
+package dev.flutter.infinite_list
 
 import io.flutter.embedding.android.FlutterActivity
 
diff --git a/infinite_list/android/app/src/main/res/drawable-v21/launch_background.xml b/infinite_list/android/app/src/main/res/drawable-v21/launch_background.xml
new file mode 100644
index 000000000..f74085f3f
--- /dev/null
+++ b/infinite_list/android/app/src/main/res/drawable-v21/launch_background.xml
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Modify this file to customize your launch splash screen -->
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:drawable="?android:colorBackground" />
+
+    <!-- You can insert your own image assets here -->
+    <!-- <item>
+        <bitmap
+            android:gravity="center"
+            android:src="@mipmap/launch_image" />
+    </item> -->
+</layer-list>
diff --git a/infinite_list/android/app/src/main/res/values-night/styles.xml b/infinite_list/android/app/src/main/res/values-night/styles.xml
new file mode 100644
index 000000000..449a9f930
--- /dev/null
+++ b/infinite_list/android/app/src/main/res/values-night/styles.xml
@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <!-- Theme applied to the Android Window while the process is starting when the OS's Dark Mode setting is on -->
+    <style name="LaunchTheme" parent="@android:style/Theme.Black.NoTitleBar">
+        <!-- Show a splash screen on the activity. Automatically removed when
+             Flutter draws its first frame -->
+        <item name="android:windowBackground">@drawable/launch_background</item>
+    </style>
+    <!-- Theme applied to the Android Window as soon as the process has started.
+         This theme determines the color of the Android Window while your
+         Flutter UI initializes, as well as behind your Flutter UI while its
+         running.
+         
+         This Theme is only used starting with V2 of Flutter's Android embedding. -->
+    <style name="NormalTheme" parent="@android:style/Theme.Black.NoTitleBar">
+        <item name="android:windowBackground">?android:colorBackground</item>
+    </style>
+</resources>
diff --git a/infinite_list/android/app/src/main/res/values/styles.xml b/infinite_list/android/app/src/main/res/values/styles.xml
index 1f83a33fd..d74aa35c2 100644
--- a/infinite_list/android/app/src/main/res/values/styles.xml
+++ b/infinite_list/android/app/src/main/res/values/styles.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
-    <!-- Theme applied to the Android Window while the process is starting -->
-    <style name="LaunchTheme" parent="@android:style/Theme.Black.NoTitleBar">
+    <!-- Theme applied to the Android Window while the process is starting when the OS's Dark Mode setting is off -->
+    <style name="LaunchTheme" parent="@android:style/Theme.Light.NoTitleBar">
         <!-- Show a splash screen on the activity. Automatically removed when
              Flutter draws its first frame -->
         <item name="android:windowBackground">@drawable/launch_background</item>
@@ -12,7 +12,7 @@
          running.
          
          This Theme is only used starting with V2 of Flutter's Android embedding. -->
-    <style name="NormalTheme" parent="@android:style/Theme.Black.NoTitleBar">
-        <item name="android:windowBackground">@android:color/white</item>
+    <style name="NormalTheme" parent="@android:style/Theme.Light.NoTitleBar">
+        <item name="android:windowBackground">?android:colorBackground</item>
     </style>
 </resources>
diff --git a/infinite_list/android/app/src/profile/AndroidManifest.xml b/infinite_list/android/app/src/profile/AndroidManifest.xml
index a6f21932c..e82654fa7 100644
--- a/infinite_list/android/app/src/profile/AndroidManifest.xml
+++ b/infinite_list/android/app/src/profile/AndroidManifest.xml
@@ -1,5 +1,5 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="dev.flutter.infinitelist">
+    package="dev.flutter.infinite_list">
     <!-- Flutter needs it to communicate with the running application
          to allow setting breakpoints, to provide hot reload, etc.
     -->
diff --git a/infinite_list/android/build.gradle b/infinite_list/android/build.gradle
index 3100ad2d5..9b6ed06eb 100644
--- a/infinite_list/android/build.gradle
+++ b/infinite_list/android/build.gradle
@@ -6,7 +6,7 @@ buildscript {
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.5.0'
+        classpath 'com.android.tools.build:gradle:4.1.0'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }
@@ -21,8 +21,6 @@ allprojects {
 rootProject.buildDir = '../build'
 subprojects {
     project.buildDir = "${rootProject.buildDir}/${project.name}"
-}
-subprojects {
     project.evaluationDependsOn(':app')
 }
 
diff --git a/infinite_list/android/gradle.properties b/infinite_list/android/gradle.properties
index a6738207f..94adc3a3f 100644
--- a/infinite_list/android/gradle.properties
+++ b/infinite_list/android/gradle.properties
@@ -1,4 +1,3 @@
 org.gradle.jvmargs=-Xmx1536M
 android.useAndroidX=true
 android.enableJetifier=true
-android.enableR8=true
diff --git a/infinite_list/android/gradle/wrapper/gradle-wrapper.properties b/infinite_list/android/gradle/wrapper/gradle-wrapper.properties
index 296b146b7..bc6a58afd 100644
--- a/infinite_list/android/gradle/wrapper/gradle-wrapper.properties
+++ b/infinite_list/android/gradle/wrapper/gradle-wrapper.properties
@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-5.6.2-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.7-all.zip
diff --git a/infinite_list/ios/.gitignore b/infinite_list/ios/.gitignore
index fe4a4744b..151026b91 100644
--- a/infinite_list/ios/.gitignore
+++ b/infinite_list/ios/.gitignore
@@ -14,11 +14,11 @@ Icon?
 profile
 xcuserdata
 **/.generated/
-Flutter/.last_build_id
 Flutter/App.framework
 Flutter/Flutter.framework
 Flutter/Flutter.podspec
 Flutter/Generated.xcconfig
+Flutter/ephemeral/
 Flutter/app.flx
 Flutter/app.zip
 Flutter/flutter_assets/
diff --git a/infinite_list/ios/Flutter/AppFrameworkInfo.plist b/infinite_list/ios/Flutter/AppFrameworkInfo.plist
index 6b4c0f78a..9367d483e 100644
--- a/infinite_list/ios/Flutter/AppFrameworkInfo.plist
+++ b/infinite_list/ios/Flutter/AppFrameworkInfo.plist
@@ -3,7 +3,7 @@
 <plist version="1.0">
 <dict>
   <key>CFBundleDevelopmentRegion</key>
-  <string>$(DEVELOPMENT_LANGUAGE)</string>
+  <string>en</string>
   <key>CFBundleExecutable</key>
   <string>App</string>
   <key>CFBundleIdentifier</key>
diff --git a/infinite_list/ios/Runner.xcodeproj/project.pbxproj b/infinite_list/ios/Runner.xcodeproj/project.pbxproj
index b36bc91d9..9e164d2a1 100644
--- a/infinite_list/ios/Runner.xcodeproj/project.pbxproj
+++ b/infinite_list/ios/Runner.xcodeproj/project.pbxproj
@@ -289,17 +289,9 @@
 				CLANG_ENABLE_MODULES = YES;
 				CURRENT_PROJECT_VERSION = "$(FLUTTER_BUILD_NUMBER)";
 				ENABLE_BITCODE = NO;
-				FRAMEWORK_SEARCH_PATHS = (
-					"$(inherited)",
-					"$(PROJECT_DIR)/Flutter",
-				);
 				INFOPLIST_FILE = Runner/Info.plist;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
-				LIBRARY_SEARCH_PATHS = (
-					"$(inherited)",
-					"$(PROJECT_DIR)/Flutter",
-				);
-				PRODUCT_BUNDLE_IDENTIFIER = dev.flutter.infinitelist;
+				PRODUCT_BUNDLE_IDENTIFIER = dev.flutter.infiniteList;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OBJC_BRIDGING_HEADER = "Runner/Runner-Bridging-Header.h";
 				SWIFT_VERSION = 5.0;
@@ -421,17 +413,9 @@
 				CLANG_ENABLE_MODULES = YES;
 				CURRENT_PROJECT_VERSION = "$(FLUTTER_BUILD_NUMBER)";
 				ENABLE_BITCODE = NO;
-				FRAMEWORK_SEARCH_PATHS = (
-					"$(inherited)",
-					"$(PROJECT_DIR)/Flutter",
-				);
 				INFOPLIST_FILE = Runner/Info.plist;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
-				LIBRARY_SEARCH_PATHS = (
-					"$(inherited)",
-					"$(PROJECT_DIR)/Flutter",
-				);
-				PRODUCT_BUNDLE_IDENTIFIER = dev.flutter.infinitelist;
+				PRODUCT_BUNDLE_IDENTIFIER = dev.flutter.infiniteList;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OBJC_BRIDGING_HEADER = "Runner/Runner-Bridging-Header.h";
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
@@ -448,17 +432,9 @@
 				CLANG_ENABLE_MODULES = YES;
 				CURRENT_PROJECT_VERSION = "$(FLUTTER_BUILD_NUMBER)";
 				ENABLE_BITCODE = NO;
-				FRAMEWORK_SEARCH_PATHS = (
-					"$(inherited)",
-					"$(PROJECT_DIR)/Flutter",
-				);
 				INFOPLIST_FILE = Runner/Info.plist;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
-				LIBRARY_SEARCH_PATHS = (
-					"$(inherited)",
-					"$(PROJECT_DIR)/Flutter",
-				);
-				PRODUCT_BUNDLE_IDENTIFIER = dev.flutter.infinitelist;
+				PRODUCT_BUNDLE_IDENTIFIER = dev.flutter.infiniteList;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OBJC_BRIDGING_HEADER = "Runner/Runner-Bridging-Header.h";
 				SWIFT_VERSION = 5.0;
diff --git a/infinite_list/ios/Runner.xcodeproj/project.xcworkspace/contents.xcworkspacedata b/infinite_list/ios/Runner.xcodeproj/project.xcworkspace/contents.xcworkspacedata
index 1d526a16e..919434a62 100644
--- a/infinite_list/ios/Runner.xcodeproj/project.xcworkspace/contents.xcworkspacedata
+++ b/infinite_list/ios/Runner.xcodeproj/project.xcworkspace/contents.xcworkspacedata
@@ -2,6 +2,6 @@
 <Workspace
    version = "1.0">
    <FileRef
-      location = "group:Runner.xcodeproj">
+      location = "self:">
    </FileRef>
 </Workspace>
diff --git a/infinite_list/ios/Runner/Info.plist b/infinite_list/ios/Runner/Info.plist
index 2dacdad17..473d3188e 100644
--- a/infinite_list/ios/Runner/Info.plist
+++ b/infinite_list/ios/Runner/Info.plist
@@ -11,7 +11,7 @@
 	<key>CFBundleInfoDictionaryVersion</key>
 	<string>6.0</string>
 	<key>CFBundleName</key>
-	<string>infinitelist</string>
+	<string>infinite_list</string>
 	<key>CFBundlePackageType</key>
 	<string>APPL</string>
 	<key>CFBundleShortVersionString</key>
diff --git a/infinite_list/lib/main.dart b/infinite_list/lib/main.dart
index 898e757e9..f59e5c059 100644
--- a/infinite_list/lib/main.dart
+++ b/infinite_list/lib/main.dart
@@ -9,15 +9,17 @@ import 'src/catalog.dart';
 import 'src/item_tile.dart';
 
 void main() {
-  runApp(MyApp());
+  runApp(const MyApp());
 }
 
 class MyApp extends StatelessWidget {
+  const MyApp({Key? key}) : super(key: key);
+
   @override
   Widget build(BuildContext context) {
     return ChangeNotifierProvider<Catalog>(
       create: (context) => Catalog(),
-      child: MaterialApp(
+      child: const MaterialApp(
         title: 'Infinite List Sample',
         home: MyHomePage(),
       ),
@@ -26,6 +28,8 @@ class MyApp extends StatelessWidget {
 }
 
 class MyHomePage extends StatelessWidget {
+  const MyHomePage({Key? key}) : super(key: key);
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
diff --git a/infinite_list/pubspec.yaml b/infinite_list/pubspec.yaml
index e662ddeb6..2f44348e8 100644
--- a/infinite_list/pubspec.yaml
+++ b/infinite_list/pubspec.yaml
@@ -13,7 +13,7 @@ dependencies:
 
   cupertino_icons: ^1.0.2
   meta: ^1.3.0
-  provider: ^5.0.0-nullsafety.3
+  provider: ^5.0.0
 
 dev_dependencies:
   flutter_test:
diff --git a/infinite_list/test/smoke_test.dart b/infinite_list/test/smoke_test.dart
index 0b22519f0..254295df0 100644
--- a/infinite_list/test/smoke_test.dart
+++ b/infinite_list/test/smoke_test.dart
@@ -9,7 +9,7 @@ import 'package:infinitelist/main.dart';
 
 void main() {
   testWidgets('Infinite list smoke test', (tester) async {
-    await tester.pumpWidget(MyApp());
+    await tester.pumpWidget(const MyApp());
 
     const loadingDuration = Duration(milliseconds: 500);
 
diff --git a/infinite_list/web/index.html b/infinite_list/web/index.html
index d2aea404b..864b27e22 100644
--- a/infinite_list/web/index.html
+++ b/infinite_list/web/index.html
@@ -1,6 +1,19 @@
 <!DOCTYPE html>
 <html>
+
 <head>
+  <!--
+    If you are serving your web app in a path other than the root, change the
+    href value below to reflect the base path you are serving from.
+
+    The path provided below has to start and end with a slash "/" in order for
+    it to work correctly.
+
+    For more details:
+    * https://developer.mozilla.org/en-US/docs/Web/HTML/Element/base
+  -->
+  <base href="/">
+
   <meta charset="UTF-8">
   <meta content="IE=Edge" http-equiv="X-UA-Compatible">
   <meta name="description" content="A new Flutter project.">
@@ -12,22 +25,80 @@
   <link rel="apple-touch-icon" href="icons/Icon-192.png">
 
   <!-- Favicon -->
-  <link rel="icon" type="image/png" href="favicon.png"/>
+  <link rel="icon" type="image/png" href="favicon.png" />
 
   <title>infinite_list</title>
   <link rel="manifest" href="manifest.json">
 </head>
+
 <body>
   <!-- This script installs service_worker.js to provide PWA functionality to
        application. For more information, see:
        https://developers.google.com/web/fundamentals/primers/service-workers -->
   <script>
+    var serviceWorkerVersion = null;
+    var scriptLoaded = false;
+    function loadMainDartJs() {
+      if (scriptLoaded) {
+        return;
+      }
+      scriptLoaded = true;
+      var scriptTag = document.createElement('script');
+      scriptTag.src = 'main.dart.js';
+      scriptTag.type = 'application/javascript';
+      document.body.append(scriptTag);
+    }
+
     if ('serviceWorker' in navigator) {
-      window.addEventListener('flutter-first-frame', function () {
-        navigator.serviceWorker.register('flutter_service_worker.js');
+      // Service workers are supported. Use them.
+      window.addEventListener('load', function () {
+        // Wait for registration to finish before dropping the <script> tag.
+        // Otherwise, the browser will load the script multiple times,
+        // potentially different versions.
+        var serviceWorkerUrl = 'flutter_service_worker.js?v=' + serviceWorkerVersion;
+        navigator.serviceWorker.register(serviceWorkerUrl)
+          .then((reg) => {
+            function waitForActivation(serviceWorker) {
+              serviceWorker.addEventListener('statechange', () => {
+                if (serviceWorker.state == 'activated') {
+                  console.log('Installed new service worker.');
+                  loadMainDartJs();
+                }
+              });
+            }
+            if (!reg.active && (reg.installing || reg.waiting)) {
+              // No active web worker and we have installed or are installing
+              // one for the first time. Simply wait for it to activate.
+              waitForActivation(reg.installing ?? reg.waiting);
+            } else if (!reg.active.scriptURL.endsWith(serviceWorkerVersion)) {
+              // When the app updates the serviceWorkerVersion changes, so we
+              // need to ask the service worker to update.
+              console.log('New service worker available.');
+              reg.update();
+              waitForActivation(reg.installing);
+            } else {
+              // Existing service worker is still good.
+              console.log('Loading app from service worker.');
+              loadMainDartJs();
+            }
+          });
+
+        // If service worker doesn't succeed in a reasonable amount of time,
+        // fallback to plaint <script> tag.
+        setTimeout(() => {
+          if (!scriptLoaded) {
+            console.warn(
+              'Failed to load app from service worker. Falling back to plain <script> tag.',
+            );
+            loadMainDartJs();
+          }
+        }, 4000);
       });
+    } else {
+      // Service workers not supported. Just drop the <script> tag.
+      loadMainDartJs();
     }
   </script>
-  <script src="main.dart.js" type="application/javascript"></script>
 </body>
-</html>
+
+</html>
\ No newline at end of file