Try fix syntax error

app.py

@@ -16,7 +16,7 @@ with gr.Blocks() as demo:  # Create a Blocks context
         iface.set_value(project_data, value=state.context) 
         iface.set_value(output, value=state.context)
       
-    iface.js_code("window.addEventListener("message", on_message);)
+    iface.js_code("window.addEventListener('message', on_message);)
 
 iface.launch( 
     server_name="0.0.0.0", # Allow external connections