diff --git a/src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java b/src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java
index 9de045f..7512ddd 100644
--- a/src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java
+++ b/src/main/java/com/flowingcode/vaadin/jsonmigration/ClassInstrumentationUtil.java
@@ -42,6 +42,8 @@
 import org.objectweb.asm.MethodVisitor;
 import org.objectweb.asm.Opcodes;
 import org.objectweb.asm.Type;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * Utility class for instrumenting classes at runtime.
@@ -57,6 +59,8 @@
  */
 final class ClassInstrumentationUtil {
 
+  private final Logger logger = LoggerFactory.getLogger(this.getClass());
+
   private final int version;
 
   private final Map<ClassLoader, InstrumentedClassLoader> classLoaderCache = new WeakHashMap<>();
@@ -115,6 +119,7 @@ public <T extends Component> Class<? extends T> instrumentClass(Class<T> parent)
     }
 
     if (!needsInstrumentation(parent)) {
+      logger.info("{} no instrumentation needed", parent);
       return parent;
     }
 
@@ -248,7 +253,8 @@ private byte[] generateBytecode(String className, Class<?> parent) {
 
       ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES | ClassWriter.COMPUTE_MAXS);
 
-      cw.visit(Opcodes.V1_8, Opcodes.ACC_PUBLIC, internalClassName, null, internalParentName, null);
+      cw.visit(Opcodes.V1_8, Opcodes.ACC_PUBLIC | Opcodes.ACC_FINAL,
+          internalClassName, null, internalParentName, null);
 
       generateConstructor(cw, internalParentName);
       generateClientCallableOverrides(cw, parent, internalClassName, internalParentName);
@@ -361,12 +367,14 @@ private void createLookupHelper(ClassWriter cw, Method method) {
     }
 
     private void generateMethodOverride(ClassWriter cw, Method method, String internalClassName, String internalParentName) {
+      logger.info("Override {}", method);
+
       boolean hasJsonValueReturn = !hasLegacyVaadin() && JsonValue.class.isAssignableFrom(method.getReturnType());
       boolean hasJsonValueParams = !hasLegacyVaadin() && hasJsonValueParameters(method);
 
       String overrideDescriptor = getMethodDescriptor(method, hasJsonValueParams);
       String superDescriptor = getMethodDescriptor(method, false);
-      int access = method.getModifiers() & (Opcodes.ACC_PUBLIC | Opcodes.ACC_PROTECTED);
+      int access = method.getModifiers() & (Opcodes.ACC_PUBLIC | Opcodes.ACC_PROTECTED | Opcodes.ACC_PRIVATE);
 
       MethodVisitor mv = cw.visitMethod(access, method.getName(), overrideDescriptor, null,
           getExceptionInternalNames(method.getExceptionTypes()));
diff --git a/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalArrayNode.java b/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalArrayNode.java
index 75a00a5..267c84f 100644
--- a/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalArrayNode.java
+++ b/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalArrayNode.java
@@ -20,6 +20,7 @@
 package com.flowingcode.vaadin.jsonmigration;
 
 import elemental.json.JsonArray;
+import elemental.json.JsonType;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
@@ -49,5 +50,10 @@ private static List<JsonNode> children(JsonArray a) {
     }
   }
 
+  @Override
+  public JsonType getType() {
+    return JsonType.ARRAY;
+  }
+
 }
 
diff --git a/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalBooleanNode.java b/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalBooleanNode.java
index b628fdc..0eca205 100644
--- a/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalBooleanNode.java
+++ b/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalBooleanNode.java
@@ -19,6 +19,7 @@
  */
 package com.flowingcode.vaadin.jsonmigration;
 
+import elemental.json.JsonType;
 import tools.jackson.databind.node.BooleanNode;
 
 @SuppressWarnings("serial")
@@ -28,6 +29,11 @@ public ElementalBooleanNode(boolean value) {
     super(value);
   }
 
+  @Override
+  public JsonType getType() {
+    return JsonType.BOOLEAN;
+  }
+
 }
 
 
diff --git a/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalNullNode.java b/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalNullNode.java
index 7c70016..a166498 100644
--- a/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalNullNode.java
+++ b/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalNullNode.java
@@ -19,6 +19,7 @@
  */
 package com.flowingcode.vaadin.jsonmigration;
 
+import elemental.json.JsonType;
 import tools.jackson.databind.node.NullNode;
 
 @SuppressWarnings("serial")
@@ -33,5 +34,10 @@ public String toJson() {
     return null;
   }
 
+  @Override
+  public JsonType getType() {
+    return JsonType.NULL;
+  }
+
 }
 
diff --git a/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalNumberNode.java b/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalNumberNode.java
index 67680cf..5d96826 100644
--- a/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalNumberNode.java
+++ b/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalNumberNode.java
@@ -19,6 +19,7 @@
  */
 package com.flowingcode.vaadin.jsonmigration;
 
+import elemental.json.JsonType;
 import tools.jackson.databind.node.DoubleNode;
 
 @SuppressWarnings("serial")
@@ -37,5 +38,11 @@ public String toJson() {
       return UnsupportedJsonValueImpl.super.toJson();
     }
   }
+
+  @Override
+  public JsonType getType() {
+    return JsonType.NUMBER;
+  }
+
 }
 
diff --git a/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalObjectNode.java b/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalObjectNode.java
index ba6e7e4..9c48f8d 100644
--- a/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalObjectNode.java
+++ b/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalObjectNode.java
@@ -21,6 +21,7 @@
 
 import static com.flowingcode.vaadin.jsonmigration.JsonMigrationHelper25.convertToJsonNode;
 import elemental.json.JsonObject;
+import elemental.json.JsonType;
 import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.Map;
@@ -51,6 +52,11 @@ private static Map<String, JsonNode> children(JsonObject o) {
     }
   }
 
+  @Override
+  public JsonType getType() {
+    return JsonType.OBJECT;
+  }
+
 }
 
 
diff --git a/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalStringNode.java b/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalStringNode.java
index 82be137..7e80173 100644
--- a/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalStringNode.java
+++ b/src/main/java/com/flowingcode/vaadin/jsonmigration/ElementalStringNode.java
@@ -19,6 +19,7 @@
  */
 package com.flowingcode.vaadin.jsonmigration;
 
+import elemental.json.JsonType;
 import tools.jackson.databind.node.StringNode;
 
 @SuppressWarnings("serial")
@@ -28,4 +29,9 @@ public ElementalStringNode(String value) {
     super(value);
   }
 
+  @Override
+  public JsonType getType() {
+    return JsonType.STRING;
+  }
+
 }
\ No newline at end of file
diff --git a/src/main/java/com/flowingcode/vaadin/jsonmigration/InstrumentationViewInitializer.java b/src/main/java/com/flowingcode/vaadin/jsonmigration/InstrumentationViewInitializer.java
index 1ade68a..281fd8f 100644
--- a/src/main/java/com/flowingcode/vaadin/jsonmigration/InstrumentationViewInitializer.java
+++ b/src/main/java/com/flowingcode/vaadin/jsonmigration/InstrumentationViewInitializer.java
@@ -22,7 +22,6 @@
 import com.vaadin.flow.component.Component;
 import com.vaadin.flow.router.RouteConfiguration;
 import com.vaadin.flow.server.VaadinServiceInitListener;
-import com.vaadin.flow.server.Version;
 
 /**
  * Abstract base class for Vaadin service initializers that register instrumented views. Subclasses
@@ -54,9 +53,7 @@ protected final void registerInstrumentedRoute(Class<? extends Component> naviga
     }
 
     String route = annotation.value();
-    if (Version.getMajorVersion() > 24) {
-      navigationTarget = JsonMigration.instrumentClass(navigationTarget);
-    }
+    navigationTarget = JsonMigration.instrumentClass(navigationTarget);
     RouteConfiguration.forApplicationScope().setRoute(route, navigationTarget);
   }
 
diff --git a/src/main/java/com/flowingcode/vaadin/jsonmigration/JsonMigrationHelper25.java b/src/main/java/com/flowingcode/vaadin/jsonmigration/JsonMigrationHelper25.java
index e4b0fb9..300bd7c 100644
--- a/src/main/java/com/flowingcode/vaadin/jsonmigration/JsonMigrationHelper25.java
+++ b/src/main/java/com/flowingcode/vaadin/jsonmigration/JsonMigrationHelper25.java
@@ -66,8 +66,8 @@ public JsonValue convertToJsonValue(Object object) {
   @SuppressWarnings("unchecked")
   @Override
   public JsonValue convertToClientCallableResult(JsonValue object) {
-    if (object == null) {
-      return null;
+    if (object == null || object instanceof JsonNode) {
+      return object;
     } else {
       switch (object.getType()) {
         case OBJECT:
diff --git a/src/main/java/com/flowingcode/vaadin/jsonmigration/UnsupportedJsonValueImpl.java b/src/main/java/com/flowingcode/vaadin/jsonmigration/UnsupportedJsonValueImpl.java
index 591dfcb..15d477c 100644
--- a/src/main/java/com/flowingcode/vaadin/jsonmigration/UnsupportedJsonValueImpl.java
+++ b/src/main/java/com/flowingcode/vaadin/jsonmigration/UnsupportedJsonValueImpl.java
@@ -19,7 +19,6 @@
  */
 package com.flowingcode.vaadin.jsonmigration;
 
-import elemental.json.JsonType;
 import elemental.json.JsonValue;
 import tools.jackson.databind.JsonNode;
 
@@ -40,11 +39,6 @@ default String asString() {
     throw new UnsupportedOperationException();
   }
 
-  @Override
-  default JsonType getType() {
-    throw new UnsupportedOperationException();
-  }
-
   @Override
   default String toJson() {
     return ((JsonNode) this).toString();