diff --git a/lib/widgets/editor.dart b/lib/widgets/editor.dart
index a2400bd5..fc950b65 100644
--- a/lib/widgets/editor.dart
+++ b/lib/widgets/editor.dart
@@ -20,15 +20,16 @@ import 'package:flutter_quill/widgets/image.dart';
 import 'package:flutter_quill/widgets/raw_editor.dart';
 import 'package:flutter_quill/widgets/responsive_widget.dart';
 import 'package:flutter_quill/widgets/text_selection.dart';
+import 'package:string_validator/string_validator.dart';
 import 'package:universal_html/prefer_universal/html.dart' as html;
 import 'package:url_launcher/url_launcher.dart';
 
-import 'FakeUi.dart' if (dart.library.html) 'RealUi.dart' as ui;
 import 'box.dart';
 import 'controller.dart';
 import 'cursor.dart';
 import 'default_styles.dart';
 import 'delegate.dart';
+import 'fake_ui.dart' if (dart.library.html) 'real_ui.dart' as ui;
 
 const urlPattern =
     r"^((https?|http)://)?([-A-Z0-9.]+)(/[-A-Z0-9+&@#/%=~_|!:,.;]*)?(\?[A-Z0-9+&@#/%=~_|!:‌​,.;]*)?$";
diff --git a/pubspec.lock b/pubspec.lock
index 59f3c93b..11822ea2 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -89,7 +89,7 @@ packages:
       name: flutter_colorpicker
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.4.0-nullsafety.0"
+    version: "0.3.5"
   flutter_keyboard_visibility:
     dependency: "direct main"
     description:
@@ -212,13 +212,20 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "2.0.0"
+  quill_delta:
+    dependency: "direct main"
+    description:
+      name: quill_delta
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.0"
   quiver:
     dependency: transitive
     description:
       name: quiver
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "3.0.0"
+    version: "2.1.5"
   quiver_hashcode:
     dependency: "direct main"
     description:
@@ -265,7 +272,7 @@ packages:
       name: string_validator
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.0-nullsafety.0"
+    version: "0.1.4"
   term_glyph:
     dependency: transitive
     description:
@@ -286,7 +293,7 @@ packages:
       name: tuple
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.0.0-nullsafety.0"
+    version: "1.0.3"
   typed_data:
     dependency: transitive
     description:
@@ -366,4 +373,4 @@ packages:
     version: "0.1.2"
 sdks:
   dart: ">=2.12.0 <3.0.0"
-  flutter: ">=1.24.0-10.2.pre"
+  flutter: ">=1.22.0"
diff --git a/pubspec.yaml b/pubspec.yaml
index 985e81cc..5101fc32 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -14,16 +14,16 @@ dependencies:
     sdk: flutter
   quill_delta: ^2.0.0
   quiver_hashcode: ^2.0.0
-  collection: ^1.14.13
+  collection: ^1.15.0
   tuple: ^1.0.3
-  url_launcher: ^5.7.10
+  url_launcher: ^6.0.2
   flutter_colorpicker: ^0.3.5
-  image_picker: ^0.6.7+22
+  image_picker: ^0.7.2
   photo_view: ^0.10.3
   universal_html: ^1.2.4
-  file_picker: ^3.0.0-nullsafety.4
-  string_validator: ^0.2.0-nullsafety.0
-  flutter_keyboard_visibility: ^5.0.0-nullsafety.2
+  file_picker: ^3.0.0
+  string_validator: ^0.1.4
+  flutter_keyboard_visibility: ^5.0.0
 
 
 dev_dependencies: