diff --git a/Assets/VRM/UniGLTF/Editor/JsonDeserializeTests.cs b/Assets/VRM/UniGLTF/Editor/JsonDeserializeTests.cs
index fcccff774..e056df6f6 100644
--- a/Assets/VRM/UniGLTF/Editor/JsonDeserializeTests.cs
+++ b/Assets/VRM/UniGLTF/Editor/JsonDeserializeTests.cs
@@ -29,7 +29,7 @@ namespace UniGLTF
             {
                 var r = deserialize<glTFPrimitives_extensions>("{\"KHR_draco_mesh_compression\":{}}");
                 Assert.NotNull(r);
-                Assert.NotNull(r.KHR_draco_mesh_compression);
+                //Assert.NotNull(r.KHR_draco_mesh_compression);
             }
         }
     }
diff --git a/Assets/VRM/UniGLTF/Editor/UniGLTFTests.cs b/Assets/VRM/UniGLTF/Editor/UniGLTFTests.cs
index f55fa3231..5df2d0a1d 100644
--- a/Assets/VRM/UniGLTF/Editor/UniGLTFTests.cs
+++ b/Assets/VRM/UniGLTF/Editor/UniGLTFTests.cs
@@ -173,7 +173,7 @@ namespace UniGLTF
                 EnableDiagnosisForNotRequiredFields = true,
             };
             var json2 = JsonSchema.FromType<glTFMesh>().Serialize(model, c);
-            Assert.AreEqual(@"{""name"":""mesh"",""primitives"":[{""mode"":0,""attributes"":{""POSITION"":0},""material"":0,""extensions"":{}}]}", json2);
+            Assert.AreEqual(@"{""name"":""mesh"",""primitives"":[{""mode"":0,""attributes"":{""POSITION"":0},""material"":0}]}", json2);
         }
 
         [Test]
@@ -203,7 +203,7 @@ namespace UniGLTF
                 EnableDiagnosisForNotRequiredFields = true,
             };
             var json2 = JsonSchema.FromType<glTFPrimitives>().Serialize(model, c);
-            Assert.AreEqual(@"{""mode"":0,""attributes"":{""POSITION"":0},""material"":0,""extras"":{""targetNames"":[""aaa""]},""extensions"":{}}", json2);
+            Assert.AreEqual(@"{""mode"":0,""attributes"":{""POSITION"":0},""material"":0,""extras"":{""targetNames"":[""aaa""]}}", json2);
         }
 
         [Test]
diff --git a/Assets/VRM/UniGLTF/Scripts/Format/ExtensionsAndExtras/KHR_draco_mesh_compression.cs b/Assets/VRM/UniGLTF/Scripts/Format/ExtensionsAndExtras/KHR_draco_mesh_compression.cs
index b304bc0a3..1e4b9ae48 100644
--- a/Assets/VRM/UniGLTF/Scripts/Format/ExtensionsAndExtras/KHR_draco_mesh_compression.cs
+++ b/Assets/VRM/UniGLTF/Scripts/Format/ExtensionsAndExtras/KHR_draco_mesh_compression.cs
@@ -4,24 +4,9 @@ using UniJSON;
 
 namespace UniGLTF
 {
-    [Serializable]
-    public class glTF_KHR_draco_mesh_compression : JsonSerializableBase
-    {
-        [JsonSchema(Required = true, Minimum = 0)]
-        public int bufferView = -1;
-        public glTFAttributes attributes;
-
-        protected override void SerializeMembers(GLTFJsonFormatter f)
-        {
-            //throw new NotImplementedException();
-        }
-    }
-
     [Serializable]
     public partial class glTFPrimitives_extensions : ExtensionsBase<glTFPrimitives_extensions>
     {
-        public glTF_KHR_draco_mesh_compression KHR_draco_mesh_compression;
-
         [JsonSerializeMembers]
         void SerializeMembers_draco(GLTFJsonFormatter f)
         {
diff --git a/Assets/VRM/UniGLTF/Scripts/Format/glTFMesh.cs b/Assets/VRM/UniGLTF/Scripts/Format/glTFMesh.cs
index 526837b9f..315041653 100644
--- a/Assets/VRM/UniGLTF/Scripts/Format/glTFMesh.cs
+++ b/Assets/VRM/UniGLTF/Scripts/Format/glTFMesh.cs
@@ -116,7 +116,7 @@ namespace UniGLTF
         public glTFPrimitives_extras extras = new glTFPrimitives_extras();
 
         [JsonSchema(SkipSchemaComparison = true)]
-        public glTFPrimitives_extensions extensions = new glTFPrimitives_extensions();
+        public glTFPrimitives_extensions extensions = null;
 
         protected override void SerializeMembers(GLTFJsonFormatter f)
         {
@@ -128,10 +128,6 @@ namespace UniGLTF
             {
                 f.Key("targets"); f.GLTFValue(targets);
             }
-            if (extensions.KHR_draco_mesh_compression != null)
-            {
-                f.Key("extensions"); f.GLTFValue(extensions);
-            }
             if (extras.targetNames.Count > 0)
             {
                 f.Key("extras"); f.GLTFValue(extras);