diff --git a/QSB/API/Messages/AddonCustomDataSyncMessage.cs b/QSB/API/Messages/AddonCustomDataSyncMessage.cs
index f36e00db..74edc5a4 100644
--- a/QSB/API/Messages/AddonCustomDataSyncMessage.cs
+++ b/QSB/API/Messages/AddonCustomDataSyncMessage.cs
@@ -7,6 +7,5 @@ namespace QSB.API.Messages;
 public class AddonCustomDataSyncMessage : QSBMessage<(uint playerId, string key, byte[] data)>
 {
 	public AddonCustomDataSyncMessage(uint playerId, string key, object data) : base((playerId, key, data.ToBytes())) { }
-
 	public override void OnReceiveRemote() => QSBPlayerManager.GetPlayer(Data.playerId).SetCustomData(Data.key, Data.data.ToObject());
 }
diff --git a/QSB/API/QSBAPI.cs b/QSB/API/QSBAPI.cs
index 13fd1cd2..c66df79f 100644
--- a/QSB/API/QSBAPI.cs
+++ b/QSB/API/QSBAPI.cs
@@ -1,9 +1,9 @@
-using System;
-using System.Linq;
-using OWML.Common;
+using OWML.Common;
 using QSB.API.Messages;
 using QSB.Messaging;
 using QSB.Player;
+using System;
+using System.Linq;
 using UnityEngine.Events;
 
 namespace QSB.API;
@@ -26,11 +26,8 @@ public class QSBAPI : IQSBAPI
 	public UnityEvent<uint> OnPlayerJoin() => QSBAPIEvents.OnPlayerJoinEvent;
 	public UnityEvent<uint> OnPlayerLeave() => QSBAPIEvents.OnPlayerLeaveEvent;
 
-	public void SetCustomData<T>(uint playerId, string key, T data) 
-		=> QSBPlayerManager.GetPlayer(playerId).SetCustomData<T>(key, data);
-
-	public T GetCustomData<T>(uint playerId, string key)
-		=> QSBPlayerManager.GetPlayer(playerId).GetCustomData<T>(key);
+	public void SetCustomData<T>(uint playerId, string key, T data) => QSBPlayerManager.GetPlayer(playerId).SetCustomData(key, data);
+	public T GetCustomData<T>(uint playerId, string key) => QSBPlayerManager.GetPlayer(playerId).GetCustomData<T>(key);
 
 	public void SendMessage<T>(string messageType, T data, uint to = uint.MaxValue, bool receiveLocally = false)
 		=> new AddonDataMessage(messageType, data, receiveLocally) { To = to }.Send();
diff --git a/QSB/Player/Messages/RequestStateResyncMessage.cs b/QSB/Player/Messages/RequestStateResyncMessage.cs
index 28f3e8fe..347e5317 100644
--- a/QSB/Player/Messages/RequestStateResyncMessage.cs
+++ b/QSB/Player/Messages/RequestStateResyncMessage.cs
@@ -53,10 +53,9 @@ public class RequestStateResyncMessage : QSBMessage
 		new PlayerInformationMessage { To = From }.Send();
 
 		// Initial sync of all custom data from APIs
-		foreach (var key in QSBPlayerManager.LocalPlayer.GetCustomDataKeys())
+		foreach (var kvp in QSBPlayerManager.LocalPlayer._customData)
 		{
-			var data = QSBPlayerManager.LocalPlayer.GetCustomData<object>(key);
-			new AddonCustomDataSyncMessage(QSBPlayerManager.LocalPlayerId, key, data) { To = From }.Send();
+			new AddonCustomDataSyncMessage(QSBPlayerManager.LocalPlayerId, kvp.Key, kvp.Value) { To = From }.Send();
 		}
 	}
 }
\ No newline at end of file
diff --git a/QSB/Player/PlayerInfo.cs b/QSB/Player/PlayerInfo.cs
index 5b2cd9f6..585ac2af 100644
--- a/QSB/Player/PlayerInfo.cs
+++ b/QSB/Player/PlayerInfo.cs
@@ -181,7 +181,8 @@ public partial class PlayerInfo
 		HUDBox.OnRespawn();
 	}
 
-	private Dictionary<string, object> _customData = new();
+	// internal for message
+	internal readonly Dictionary<string, object> _customData = new();
 
 	public void SetCustomData<T>(string key, T data)
 	{
@@ -193,7 +194,6 @@ public partial class PlayerInfo
 		}
 	}
 
-
 	public T GetCustomData<T>(string key)
 	{
 		if (!_customData.TryGetValue(key, out var value))
@@ -204,7 +204,5 @@ public partial class PlayerInfo
 		return (T)value;
 	}
 
-	public IEnumerable<string> GetCustomDataKeys() => _customData.Keys;
-
 	public override string ToString() => $"{PlayerId}:{GetType().Name} ({Name})";
 }
diff --git a/QSB/Utility/Extensions.cs b/QSB/Utility/Extensions.cs
index d3d591bf..9677e30c 100644
--- a/QSB/Utility/Extensions.cs
+++ b/QSB/Utility/Extensions.cs
@@ -239,6 +239,9 @@ public static class Extensions
 		return sb.ToString();
 	}
 
+	/// <summary>
+	/// only works for c# serializable objects
+	/// </summary>
 	public static byte[] ToBytes(this object obj)
 	{
 		using var ms = new MemoryStream();
@@ -248,6 +251,9 @@ public static class Extensions
 		return bytes;
 	}
 
+	/// <summary>
+	/// only works for c# serializable objects
+	/// </summary>
 	public static object ToObject(this byte[] bytes)
 	{
 		using var ms = new MemoryStream(bytes);