In a chat session, the chat session progresses normally. Once the chat sequence finishes, there is no way to restart the chat. Everything is grayed out and the top end chat button is also grayed out. Refreshing the browser pages bring the chat back to the starting point.
The expected behavior should be that you should be able to click at the bottom of the chat or at the top icon to start a new chat session.
Confirmed in Paris
A custom greeting topic was using vaSystem.switchTopic. This does not enable you to restart the conversation when reaching the end.
Using vaSystem.switchTopicByName instead of vaSystem.switchTopic enables the cancel/new conversation button once a topic is in process.