This information is not very informative for us, unfortunately we cannot detect what exactly the user is doing that leads to an empty message.
The only thing I found that can lead to an empty message is a call. Because the call cannot be received in the chatboard.
But we have a trigger for the call - "call-started". The screenshot will show how it can be used. If the user is in the chat and makes a call, the chatbot will forward to such a trigger.
If you have any ideas why empty messages may still appear, please let us know.
