diff --git a/src/main/java/com/flowingcode/vaadin/addons/demo/MultiSourceCodeViewer.java b/src/main/java/com/flowingcode/vaadin/addons/demo/MultiSourceCodeViewer.java
index 2b7110b..cbdf2d5 100644
--- a/src/main/java/com/flowingcode/vaadin/addons/demo/MultiSourceCodeViewer.java
+++ b/src/main/java/com/flowingcode/vaadin/addons/demo/MultiSourceCodeViewer.java
@@ -28,7 +28,9 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
+import lombok.experimental.ExtensionMethod;
 
+@ExtensionMethod(value = JsonMigration.class, suppressBaseMethods = true)
 public class MultiSourceCodeViewer extends Div {
 
   private static final String DATA_URL = "source-url";
@@ -47,7 +49,7 @@ public MultiSourceCodeViewer(List<SourceCodeTab> sourceCodeTabs, Map<String, Str
       selectedTab = tabs.getSelectedTab();
 
       getElement().addEventListener("fragment-request", ev -> {
-        JsonValue filename = JsonMigration.getEventData(ev).get("event.detail.filename");
+        JsonValue filename = ev.getEventData().get("event.detail.filename");
         findTabWithFilename(Optional.ofNullable(filename).map(JsonValue::asString).orElse(null))
             .ifPresent(tab -> {
           tabs.setSelectedTab(tab);
diff --git a/src/main/java/com/flowingcode/vaadin/addons/demo/SourceCodeViewer.java b/src/main/java/com/flowingcode/vaadin/addons/demo/SourceCodeViewer.java
index 82d59e4..bfb3e45 100644
--- a/src/main/java/com/flowingcode/vaadin/addons/demo/SourceCodeViewer.java
+++ b/src/main/java/com/flowingcode/vaadin/addons/demo/SourceCodeViewer.java
@@ -33,9 +33,11 @@
 import elemental.json.Json;
 import elemental.json.JsonObject;
 import java.util.Map;
+import lombok.experimental.ExtensionMethod;
 
 @SuppressWarnings("serial")
 @JsModule("./code-viewer.ts")
+@ExtensionMethod(value = JsonMigration.class, suppressBaseMethods = true)
 public class SourceCodeViewer extends Div implements HasSize {
 
   private final Element codeViewer;
@@ -86,7 +88,7 @@ private void setProperties(Map<String, String> properties) {
           env.put(k, Json.create(v));
         }
       });
-      JsonMigration.setPropertyJson(codeViewer, "env", env);
+      codeViewer.setPropertyJson("env", env);
     }
   }