diff --git a/example/lib/theme.dart b/example/lib/theme.dart
index 53f9a9cb..09b6fca8 100644
--- a/example/lib/theme.dart
+++ b/example/lib/theme.dart
@@ -44,7 +44,7 @@ class LiveKitTheme {
             // backgroundColor: WidgetStateProperty.all<Color>(accentColor),
             backgroundColor: WidgetStateProperty.resolveWith((states) {
               if (states.contains(WidgetState.disabled)) {
-                return accentColor.withOpacity(0.5);
+                return accentColor.withValues(alpha: 0.5);
               }
               return accentColor;
             }),
@@ -59,13 +59,13 @@ class LiveKitTheme {
             if (states.contains(WidgetState.selected)) {
               return accentColor;
             }
-            return accentColor.withOpacity(0.3);
+            return accentColor.withValues(alpha: 0.3);
           }),
           thumbColor: WidgetStateProperty.resolveWith((states) {
             if (states.contains(WidgetState.selected)) {
               return Colors.white;
             }
-            return Colors.white.withOpacity(0.3);
+            return Colors.white.withValues(alpha: 0.3);
           }),
         ),
         dialogTheme: DialogTheme(
@@ -87,7 +87,7 @@ class LiveKitTheme {
             color: LKColors.lkBlue,
           ),
           hintStyle: TextStyle(
-            color: LKColors.lkBlue.withOpacity(.5),
+            color: LKColors.lkBlue.withValues(alpha: 5),
           ),
           enabledBorder: InputBorder.none,
           focusedBorder: InputBorder.none,
diff --git a/example/lib/widgets/participant.dart b/example/lib/widgets/participant.dart
index 1e090646..488d1132 100644
--- a/example/lib/widgets/participant.dart
+++ b/example/lib/widgets/participant.dart
@@ -176,19 +176,19 @@ abstract class _ParticipantWidgetState<T extends ParticipantWidget>
                   right: 30,
                   child: ParticipantStatsWidget(
                     participant: widget.participant,
-                  )), 
-           if(activeAudioTrack != null && !activeAudioTrack!.muted) Positioned(
-            top: 10,
-            right: 10,
-            left: 10,
-            bottom: 10,
-            child: SoundWaveformWidget(
-              key: ValueKey(activeAudioTrack!.hashCode),
-              audioTrack: activeAudioTrack!,
-              width: 8,
-            ),
-          ),
-          
+                  )),
+            if (activeAudioTrack != null && !activeAudioTrack!.muted)
+              Positioned(
+                top: 10,
+                right: 10,
+                left: 10,
+                bottom: 10,
+                child: SoundWaveformWidget(
+                  key: ValueKey(activeAudioTrack!.hashCode),
+                  audioTrack: activeAudioTrack!,
+                  width: 8,
+                ),
+              ),
           ],
         ),
       );
@@ -279,7 +279,7 @@ class RemoteTrackPublicationMenuWidget extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) => Material(
-        color: Colors.black.withOpacity(0.3),
+        color: Colors.black.withValues(alpha: 0.3),
         child: PopupMenuButton<Function>(
           tooltip: 'Subscribe menu',
           icon: Icon(icon,
@@ -317,7 +317,7 @@ class RemoteTrackFPSMenuWidget extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) => Material(
-        color: Colors.black.withOpacity(0.3),
+        color: Colors.black.withValues(alpha: 0.3),
         child: PopupMenuButton<Function>(
           tooltip: 'Preferred FPS',
           icon: Icon(icon, color: Colors.white),
@@ -351,7 +351,7 @@ class RemoteTrackQualityMenuWidget extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) => Material(
-        color: Colors.black.withOpacity(0.3),
+        color: Colors.black.withValues(alpha: 0.3),
         child: PopupMenuButton<Function>(
           tooltip: 'Preferred Quality',
           icon: Icon(icon, color: Colors.white),
@@ -373,4 +373,3 @@ class RemoteTrackQualityMenuWidget extends StatelessWidget {
         ),
       );
 }
-
diff --git a/example/lib/widgets/participant_info.dart b/example/lib/widgets/participant_info.dart
index 52a40f2a..1064b5fe 100644
--- a/example/lib/widgets/participant_info.dart
+++ b/example/lib/widgets/participant_info.dart
@@ -43,7 +43,7 @@ class ParticipantInfoWidget extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) => Container(
-        color: Colors.black.withOpacity(0.3),
+        color: Colors.black.withValues(alpha: 0.3),
         padding: const EdgeInsets.symmetric(
           vertical: 7,
           horizontal: 10,
diff --git a/example/lib/widgets/participant_stats.dart b/example/lib/widgets/participant_stats.dart
index c6342707..09231fc1 100644
--- a/example/lib/widgets/participant_stats.dart
+++ b/example/lib/widgets/participant_stats.dart
@@ -148,7 +148,7 @@ class _ParticipantStatsWidgetState extends State<ParticipantStatsWidget> {
   @override
   Widget build(BuildContext context) {
     return Container(
-      color: Colors.black.withOpacity(0.3),
+      color: Colors.black.withValues(alpha: 0.3),
       padding: const EdgeInsets.symmetric(
         vertical: 8,
         horizontal: 8,
diff --git a/example/lib/widgets/text_field.dart b/example/lib/widgets/text_field.dart
index db9c42d6..f4173f3d 100644
--- a/example/lib/widgets/text_field.dart
+++ b/example/lib/widgets/text_field.dart
@@ -31,7 +31,7 @@ class LKTextField extends StatelessWidget {
             decoration: BoxDecoration(
               border: Border.all(
                 width: 1,
-                color: Colors.white.withOpacity(.3),
+                color: Colors.white.withValues(alpha: .3),
               ),
               borderRadius: BorderRadius.circular(8),
             ),
diff --git a/lib/src/core/engine.dart b/lib/src/core/engine.dart
index c5ebe68f..be15ebf8 100644
--- a/lib/src/core/engine.dart
+++ b/lib/src/core/engine.dart
@@ -1087,12 +1087,10 @@ extension EnginePrivateMethods on Engine {
 
 extension EngineInternalMethods on Engine {
   @internal
-  List<lk_rtc.DataChannelInfo> dataChannelInfo() =>
-      [_reliableDCPub, _lossyDCPub]
-          .whereNotNull()
-          .where((e) => e.id != -1)
-          .map((e) => e.toLKInfoType())
-          .toList();
+  List<lk_rtc.DataChannelInfo> dataChannelInfo() => [
+        _reliableDCPub,
+        _lossyDCPub
+      ].nonNulls.where((e) => e.id != -1).map((e) => e.toLKInfoType()).toList();
   @internal
   Future<rtc.RTCRtpSender> createSimulcastTransceiverSender(
     LocalVideoTrack track,
diff --git a/lib/src/publication/remote.dart b/lib/src/publication/remote.dart
index bcb03d6c..5daa170f 100644
--- a/lib/src/publication/remote.dart
+++ b/lib/src/publication/remote.dart
@@ -17,7 +17,6 @@ import 'dart:math';
 
 import 'package:flutter/widgets.dart';
 
-import 'package:collection/collection.dart';
 import 'package:meta/meta.dart';
 
 import '../core/signal_client.dart';
@@ -155,9 +154,9 @@ class RemoteTrackPublication<T extends RemoteTrack>
     // filter visible build contexts
     final viewSizes = videoTrack.viewKeys
         .map((e) => e.currentContext)
-        .whereNotNull()
+        .nonNulls
         .map((e) => e.findRenderObject() as RenderBox?)
-        .whereNotNull()
+        .nonNulls
         .where((e) => e.hasSize)
         .map((e) => e.size);