test: let's see what will happen if we pass not a list of two but a list of one

app.py

@@ -275,7 +275,7 @@ class ChatInterface(gr.ChatInterface):
                 self.fn, *inputs, limiter=self.limiter
             )
 
-        history.append([message, response])
+        history.append([message+response])
         return history, history
 
 chat_interface = ChatInterface(