diff --git a/Assets/Mirror/Runtime/NetworkWriter.cs b/Assets/Mirror/Runtime/NetworkWriter.cs
index 1f74b24fb..442075f06 100644
--- a/Assets/Mirror/Runtime/NetworkWriter.cs
+++ b/Assets/Mirror/Runtime/NetworkWriter.cs
@@ -1,21 +1,10 @@
 using System;
-using System.Collections.Generic;
 using System.Runtime.CompilerServices;
-using System.Runtime.InteropServices;
-using System.Text;
 using Unity.Collections.LowLevel.Unsafe;
 using UnityEngine;
 
 namespace Mirror
 {
-    /// <summary>Helper class that weaver populates with all writer types.</summary>
-    // Note that c# creates a different static variable for each type
-    // -> Weaver.ReaderWriterProcessor.InitializeReaderAndWriters() populates it
-    public static class Writer<T>
-    {
-        public static Action<NetworkWriter, T> write;
-    }
-
     /// <summary>Network Writer for most simple types like floats, ints, buffers, structs, etc. Use NetworkWriterPool.GetReader() to avoid allocations.</summary>
     public class NetworkWriter
     {
@@ -188,412 +177,11 @@ public void Write<T>(T value)
         }
     }
 
-    // Mirror's Weaver automatically detects all NetworkWriter function types,
-    // but they do all need to be extensions.
-    public static class NetworkWriterExtensions
+    /// <summary>Helper class that weaver populates with all writer types.</summary>
+    // Note that c# creates a different static variable for each type
+    // -> Weaver.ReaderWriterProcessor.InitializeReaderAndWriters() populates it
+    public static class Writer<T>
     {
-        // cache encoding instead of creating it with BinaryWriter each time
-        // 1000 readers before:  1MB GC, 30ms
-        // 1000 readers after: 0.8MB GC, 18ms
-        static readonly UTF8Encoding encoding = new UTF8Encoding(false, true);
-        static readonly byte[] stringBuffer = new byte[NetworkWriter.MaxStringLength];
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteByte(this NetworkWriter writer, byte value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteByteNullable(this NetworkWriter writer, byte? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteSByte(this NetworkWriter writer, sbyte value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteSByteNullable(this NetworkWriter writer, sbyte? value) => writer.WriteBlittableNullable(value);
-
-        // char is not blittable. convert to ushort.
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteChar(this NetworkWriter writer, char value) => writer.WriteBlittable((ushort)value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteCharNullable(this NetworkWriter writer, char? value) => writer.WriteBlittableNullable((ushort?)value);
-
-        // bool is not blittable. convert to byte.
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteBool(this NetworkWriter writer, bool value) => writer.WriteBlittable((byte)(value ? 1 : 0));
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteBoolNullable(this NetworkWriter writer, bool? value) => writer.WriteBlittableNullable(value.HasValue ? ((byte)(value.Value ? 1 : 0)) : new byte?());
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteShort(this NetworkWriter writer, short value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteShortNullable(this NetworkWriter writer, short? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteUShort(this NetworkWriter writer, ushort value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteUShortNullable(this NetworkWriter writer, ushort? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteInt(this NetworkWriter writer, int value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteIntNullable(this NetworkWriter writer, int? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteUInt(this NetworkWriter writer, uint value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteUIntNullable(this NetworkWriter writer, uint? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteLong(this NetworkWriter writer, long value)  => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteLongNullable(this NetworkWriter writer, long? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteULong(this NetworkWriter writer, ulong value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteULongNullable(this NetworkWriter writer, ulong? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteFloat(this NetworkWriter writer, float value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteFloatNullable(this NetworkWriter writer, float? value) => writer.WriteBlittableNullable(value);
-
-        [StructLayout(LayoutKind.Explicit)]
-        internal struct UIntDouble
-        {
-            [FieldOffset(0)]
-            public double doubleValue;
-
-            [FieldOffset(0)]
-            public ulong longValue;
-        }
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteDouble(this NetworkWriter writer, double value)
-        {
-            // DEBUG: try to find the exact value that fails.
-            //UIntDouble convert = new UIntDouble{doubleValue = value};
-            //Debug.Log($"=> NetworkWriter.WriteDouble: {value} => 0x{convert.longValue:X8}");
-
-
-            writer.WriteBlittable(value);
-        }
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteDoubleNullable(this NetworkWriter writer, double? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteDecimal(this NetworkWriter writer, decimal value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteDecimalNullable(this NetworkWriter writer, decimal? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteString(this NetworkWriter writer, string value)
-        {
-            // write 0 for null support, increment real size by 1
-            // (note: original HLAPI would write "" for null strings, but if a
-            //        string is null on the server then it should also be null
-            //        on the client)
-            if (value == null)
-            {
-                writer.WriteUShort(0);
-                return;
-            }
-
-            // write string with same method as NetworkReader
-            // convert to byte[]
-            int size = encoding.GetBytes(value, 0, value.Length, stringBuffer, 0);
-
-            // check if within max size
-            if (size >= NetworkWriter.MaxStringLength)
-            {
-                throw new IndexOutOfRangeException($"NetworkWriter.Write(string) too long: {size}. Limit: {NetworkWriter.MaxStringLength}");
-            }
-
-            // write size and bytes
-            writer.WriteUShort(checked((ushort)(size + 1)));
-            writer.WriteBytes(stringBuffer, 0, size);
-        }
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteBytesAndSizeSegment(this NetworkWriter writer, ArraySegment<byte> buffer)
-        {
-            writer.WriteBytesAndSize(buffer.Array, buffer.Offset, buffer.Count);
-        }
-
-        // Weaver needs a write function with just one byte[] parameter
-        // (we don't name it .Write(byte[]) because it's really a WriteBytesAndSize since we write size / null info too)
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteBytesAndSize(this NetworkWriter writer, byte[] buffer)
-        {
-            // buffer might be null, so we can't use .Length in that case
-            writer.WriteBytesAndSize(buffer, 0, buffer != null ? buffer.Length : 0);
-        }
-
-        // for byte arrays with dynamic size, where the reader doesn't know how many will come
-        // (like an inventory with different items etc.)
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteBytesAndSize(this NetworkWriter writer, byte[] buffer, int offset, int count)
-        {
-            // null is supported because [SyncVar]s might be structs with null byte[] arrays
-            // write 0 for null array, increment normal size by 1 to save bandwidth
-            // (using size=-1 for null would limit max size to 32kb instead of 64kb)
-            if (buffer == null)
-            {
-                writer.WriteUInt(0u);
-                return;
-            }
-            writer.WriteUInt(checked((uint)count) + 1u);
-            writer.WriteBytes(buffer, offset, count);
-        }
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteArraySegment<T>(this NetworkWriter writer, ArraySegment<T> segment)
-        {
-            int length = segment.Count;
-            writer.WriteInt(length);
-            for (int i = 0; i < length; i++)
-            {
-                writer.Write(segment.Array[segment.Offset + i]);
-            }
-        }
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteVector2(this NetworkWriter writer, Vector2 value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteVector2Nullable(this NetworkWriter writer, Vector2? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteVector3(this NetworkWriter writer, Vector3 value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteVector3Nullable(this NetworkWriter writer, Vector3? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteVector4(this NetworkWriter writer, Vector4 value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteVector4Nullable(this NetworkWriter writer, Vector4? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteVector2Int(this NetworkWriter writer, Vector2Int value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteVector2IntNullable(this NetworkWriter writer, Vector2Int? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteVector3Int(this NetworkWriter writer, Vector3Int value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteVector3IntNullable(this NetworkWriter writer, Vector3Int? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteColor(this NetworkWriter writer, Color value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteColorNullable(this NetworkWriter writer, Color? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteColor32(this NetworkWriter writer, Color32 value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteColor32Nullable(this NetworkWriter writer, Color32? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteQuaternion(this NetworkWriter writer, Quaternion value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteQuaternionNullable(this NetworkWriter writer, Quaternion? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteRect(this NetworkWriter writer, Rect value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteRectNullable(this NetworkWriter writer, Rect? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WritePlane(this NetworkWriter writer, Plane value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WritePlaneNullable(this NetworkWriter writer, Plane? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteRay(this NetworkWriter writer, Ray value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteRayNullable(this NetworkWriter writer, Ray? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteMatrix4x4(this NetworkWriter writer, Matrix4x4 value) => writer.WriteBlittable(value);
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteMatrix4x4Nullable(this NetworkWriter writer, Matrix4x4? value) => writer.WriteBlittableNullable(value);
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteGuid(this NetworkWriter writer, Guid value)
-        {
-            byte[] data = value.ToByteArray();
-            writer.WriteBytes(data, 0, data.Length);
-        }
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteGuidNullable(this NetworkWriter writer, Guid? value)
-        {
-            writer.WriteBool(value.HasValue);
-            if (value.HasValue)
-                writer.WriteGuid(value.Value);
-        }
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteNetworkIdentity(this NetworkWriter writer, NetworkIdentity value)
-        {
-            if (value == null)
-            {
-                writer.WriteUInt(0);
-                return;
-            }
-            writer.WriteUInt(value.netId);
-        }
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteNetworkBehaviour(this NetworkWriter writer, NetworkBehaviour value)
-        {
-            if (value == null)
-            {
-                writer.WriteUInt(0);
-                return;
-            }
-            writer.WriteUInt(value.netId);
-            writer.WriteByte((byte)value.ComponentIndex);
-        }
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteTransform(this NetworkWriter writer, Transform value)
-        {
-            if (value == null)
-            {
-                writer.WriteUInt(0);
-                return;
-            }
-            NetworkIdentity identity = value.GetComponent<NetworkIdentity>();
-            if (identity != null)
-            {
-                writer.WriteUInt(identity.netId);
-            }
-            else
-            {
-                Debug.LogWarning($"NetworkWriter {value} has no NetworkIdentity");
-                writer.WriteUInt(0);
-            }
-        }
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteGameObject(this NetworkWriter writer, GameObject value)
-        {
-            if (value == null)
-            {
-                writer.WriteUInt(0);
-                return;
-            }
-            NetworkIdentity identity = value.GetComponent<NetworkIdentity>();
-            if (identity != null)
-            {
-                writer.WriteUInt(identity.netId);
-            }
-            else
-            {
-                Debug.LogWarning($"NetworkWriter {value} has no NetworkIdentity");
-                writer.WriteUInt(0);
-            }
-        }
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteList<T>(this NetworkWriter writer, List<T> list)
-        {
-            if (list is null)
-            {
-                writer.WriteInt(-1);
-                return;
-            }
-            writer.WriteInt(list.Count);
-            for (int i = 0; i < list.Count; i++)
-                writer.Write(list[i]);
-        }
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteArray<T>(this NetworkWriter writer, T[] array)
-        {
-            if (array is null)
-            {
-                writer.WriteInt(-1);
-                return;
-            }
-            writer.WriteInt(array.Length);
-            for (int i = 0; i < array.Length; i++)
-                writer.Write(array[i]);
-        }
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteUri(this NetworkWriter writer, Uri uri)
-        {
-            writer.WriteString(uri?.ToString());
-        }
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteTexture2D(this NetworkWriter writer, Texture2D texture2D)
-        {
-            writer.Write(texture2D.GetPixels32());
-        }
-
-
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteSprite(this NetworkWriter writer, Sprite sprite)
-        {
-            writer.WriteTexture2D(sprite.texture);
-            writer.WriteRect(sprite.rect);
-            writer.WriteVector2(sprite.pivot);
-        }
+        public static Action<NetworkWriter, T> write;
     }
 }
diff --git a/Assets/Mirror/Runtime/NetworkWriterExtensions.cs b/Assets/Mirror/Runtime/NetworkWriterExtensions.cs
new file mode 100644
index 000000000..8a596c92a
--- /dev/null
+++ b/Assets/Mirror/Runtime/NetworkWriterExtensions.cs
@@ -0,0 +1,418 @@
+using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+using System.Text;
+using UnityEngine;
+
+namespace Mirror
+{
+    // Mirror's Weaver automatically detects all NetworkWriter function types,
+    // but they do all need to be extensions.
+    public static class NetworkWriterExtensions
+    {
+        // cache encoding instead of creating it with BinaryWriter each time
+        // 1000 readers before:  1MB GC, 30ms
+        // 1000 readers after: 0.8MB GC, 18ms
+        static readonly UTF8Encoding encoding = new UTF8Encoding(false, true);
+        static readonly byte[] stringBuffer = new byte[NetworkWriter.MaxStringLength];
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteByte(this NetworkWriter writer, byte value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteByteNullable(this NetworkWriter writer, byte? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteSByte(this NetworkWriter writer, sbyte value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteSByteNullable(this NetworkWriter writer, sbyte? value) => writer.WriteBlittableNullable(value);
+
+        // char is not blittable. convert to ushort.
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteChar(this NetworkWriter writer, char value) => writer.WriteBlittable((ushort)value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteCharNullable(this NetworkWriter writer, char? value) => writer.WriteBlittableNullable((ushort?)value);
+
+        // bool is not blittable. convert to byte.
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteBool(this NetworkWriter writer, bool value) => writer.WriteBlittable((byte)(value ? 1 : 0));
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteBoolNullable(this NetworkWriter writer, bool? value) => writer.WriteBlittableNullable(value.HasValue ? ((byte)(value.Value ? 1 : 0)) : new byte?());
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteShort(this NetworkWriter writer, short value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteShortNullable(this NetworkWriter writer, short? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteUShort(this NetworkWriter writer, ushort value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteUShortNullable(this NetworkWriter writer, ushort? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteInt(this NetworkWriter writer, int value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteIntNullable(this NetworkWriter writer, int? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteUInt(this NetworkWriter writer, uint value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteUIntNullable(this NetworkWriter writer, uint? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteLong(this NetworkWriter writer, long value)  => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteLongNullable(this NetworkWriter writer, long? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteULong(this NetworkWriter writer, ulong value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteULongNullable(this NetworkWriter writer, ulong? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteFloat(this NetworkWriter writer, float value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteFloatNullable(this NetworkWriter writer, float? value) => writer.WriteBlittableNullable(value);
+
+        [StructLayout(LayoutKind.Explicit)]
+        internal struct UIntDouble
+        {
+            [FieldOffset(0)]
+            public double doubleValue;
+
+            [FieldOffset(0)]
+            public ulong longValue;
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteDouble(this NetworkWriter writer, double value)
+        {
+            // DEBUG: try to find the exact value that fails.
+            //UIntDouble convert = new UIntDouble{doubleValue = value};
+            //Debug.Log($"=> NetworkWriter.WriteDouble: {value} => 0x{convert.longValue:X8}");
+
+
+            writer.WriteBlittable(value);
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteDoubleNullable(this NetworkWriter writer, double? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteDecimal(this NetworkWriter writer, decimal value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteDecimalNullable(this NetworkWriter writer, decimal? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteString(this NetworkWriter writer, string value)
+        {
+            // write 0 for null support, increment real size by 1
+            // (note: original HLAPI would write "" for null strings, but if a
+            //        string is null on the server then it should also be null
+            //        on the client)
+            if (value == null)
+            {
+                writer.WriteUShort(0);
+                return;
+            }
+
+            // write string with same method as NetworkReader
+            // convert to byte[]
+            int size = encoding.GetBytes(value, 0, value.Length, stringBuffer, 0);
+
+            // check if within max size
+            if (size >= NetworkWriter.MaxStringLength)
+            {
+                throw new IndexOutOfRangeException($"NetworkWriter.Write(string) too long: {size}. Limit: {NetworkWriter.MaxStringLength}");
+            }
+
+            // write size and bytes
+            writer.WriteUShort(checked((ushort)(size + 1)));
+            writer.WriteBytes(stringBuffer, 0, size);
+        }
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteBytesAndSizeSegment(this NetworkWriter writer, ArraySegment<byte> buffer)
+        {
+            writer.WriteBytesAndSize(buffer.Array, buffer.Offset, buffer.Count);
+        }
+
+        // Weaver needs a write function with just one byte[] parameter
+        // (we don't name it .Write(byte[]) because it's really a WriteBytesAndSize since we write size / null info too)
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteBytesAndSize(this NetworkWriter writer, byte[] buffer)
+        {
+            // buffer might be null, so we can't use .Length in that case
+            writer.WriteBytesAndSize(buffer, 0, buffer != null ? buffer.Length : 0);
+        }
+
+        // for byte arrays with dynamic size, where the reader doesn't know how many will come
+        // (like an inventory with different items etc.)
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteBytesAndSize(this NetworkWriter writer, byte[] buffer, int offset, int count)
+        {
+            // null is supported because [SyncVar]s might be structs with null byte[] arrays
+            // write 0 for null array, increment normal size by 1 to save bandwidth
+            // (using size=-1 for null would limit max size to 32kb instead of 64kb)
+            if (buffer == null)
+            {
+                writer.WriteUInt(0u);
+                return;
+            }
+            writer.WriteUInt(checked((uint)count) + 1u);
+            writer.WriteBytes(buffer, offset, count);
+        }
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteArraySegment<T>(this NetworkWriter writer, ArraySegment<T> segment)
+        {
+            int length = segment.Count;
+            writer.WriteInt(length);
+            for (int i = 0; i < length; i++)
+            {
+                writer.Write(segment.Array[segment.Offset + i]);
+            }
+        }
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteVector2(this NetworkWriter writer, Vector2 value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteVector2Nullable(this NetworkWriter writer, Vector2? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteVector3(this NetworkWriter writer, Vector3 value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteVector3Nullable(this NetworkWriter writer, Vector3? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteVector4(this NetworkWriter writer, Vector4 value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteVector4Nullable(this NetworkWriter writer, Vector4? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteVector2Int(this NetworkWriter writer, Vector2Int value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteVector2IntNullable(this NetworkWriter writer, Vector2Int? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteVector3Int(this NetworkWriter writer, Vector3Int value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteVector3IntNullable(this NetworkWriter writer, Vector3Int? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteColor(this NetworkWriter writer, Color value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteColorNullable(this NetworkWriter writer, Color? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteColor32(this NetworkWriter writer, Color32 value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteColor32Nullable(this NetworkWriter writer, Color32? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteQuaternion(this NetworkWriter writer, Quaternion value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteQuaternionNullable(this NetworkWriter writer, Quaternion? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteRect(this NetworkWriter writer, Rect value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteRectNullable(this NetworkWriter writer, Rect? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WritePlane(this NetworkWriter writer, Plane value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WritePlaneNullable(this NetworkWriter writer, Plane? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteRay(this NetworkWriter writer, Ray value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteRayNullable(this NetworkWriter writer, Ray? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteMatrix4x4(this NetworkWriter writer, Matrix4x4 value) => writer.WriteBlittable(value);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteMatrix4x4Nullable(this NetworkWriter writer, Matrix4x4? value) => writer.WriteBlittableNullable(value);
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteGuid(this NetworkWriter writer, Guid value)
+        {
+            byte[] data = value.ToByteArray();
+            writer.WriteBytes(data, 0, data.Length);
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteGuidNullable(this NetworkWriter writer, Guid? value)
+        {
+            writer.WriteBool(value.HasValue);
+            if (value.HasValue)
+                writer.WriteGuid(value.Value);
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteNetworkIdentity(this NetworkWriter writer, NetworkIdentity value)
+        {
+            if (value == null)
+            {
+                writer.WriteUInt(0);
+                return;
+            }
+            writer.WriteUInt(value.netId);
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteNetworkBehaviour(this NetworkWriter writer, NetworkBehaviour value)
+        {
+            if (value == null)
+            {
+                writer.WriteUInt(0);
+                return;
+            }
+            writer.WriteUInt(value.netId);
+            writer.WriteByte((byte)value.ComponentIndex);
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteTransform(this NetworkWriter writer, Transform value)
+        {
+            if (value == null)
+            {
+                writer.WriteUInt(0);
+                return;
+            }
+            NetworkIdentity identity = value.GetComponent<NetworkIdentity>();
+            if (identity != null)
+            {
+                writer.WriteUInt(identity.netId);
+            }
+            else
+            {
+                Debug.LogWarning($"NetworkWriter {value} has no NetworkIdentity");
+                writer.WriteUInt(0);
+            }
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteGameObject(this NetworkWriter writer, GameObject value)
+        {
+            if (value == null)
+            {
+                writer.WriteUInt(0);
+                return;
+            }
+            NetworkIdentity identity = value.GetComponent<NetworkIdentity>();
+            if (identity != null)
+            {
+                writer.WriteUInt(identity.netId);
+            }
+            else
+            {
+                Debug.LogWarning($"NetworkWriter {value} has no NetworkIdentity");
+                writer.WriteUInt(0);
+            }
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteList<T>(this NetworkWriter writer, List<T> list)
+        {
+            if (list is null)
+            {
+                writer.WriteInt(-1);
+                return;
+            }
+            writer.WriteInt(list.Count);
+            for (int i = 0; i < list.Count; i++)
+                writer.Write(list[i]);
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteArray<T>(this NetworkWriter writer, T[] array)
+        {
+            if (array is null)
+            {
+                writer.WriteInt(-1);
+                return;
+            }
+            writer.WriteInt(array.Length);
+            for (int i = 0; i < array.Length; i++)
+                writer.Write(array[i]);
+        }
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteUri(this NetworkWriter writer, Uri uri)
+        {
+            writer.WriteString(uri?.ToString());
+        }
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteTexture2D(this NetworkWriter writer, Texture2D texture2D)
+        {
+            writer.Write(texture2D.GetPixels32());
+        }
+
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static void WriteSprite(this NetworkWriter writer, Sprite sprite)
+        {
+            writer.WriteTexture2D(sprite.texture);
+            writer.WriteRect(sprite.rect);
+            writer.WriteVector2(sprite.pivot);
+        }
+    }
+}
diff --git a/Assets/Mirror/Runtime/NetworkWriterExtensions.cs.meta b/Assets/Mirror/Runtime/NetworkWriterExtensions.cs.meta
new file mode 100644
index 000000000..f7c367976
--- /dev/null
+++ b/Assets/Mirror/Runtime/NetworkWriterExtensions.cs.meta
@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: 94259792df2a404892c3e2377f58d0cb
+timeCreated: 1644998104
\ No newline at end of file