Is your feature request related to a problem? Please describe.
When I close a livechat conversation, I always have to insert a closing comment, which frustrates me since we do not use these comments at all.

Describe the solution you'd like
As livechat admin I really like to decide wether this comment is optional or not relevant at all. If it is not relevant at all, the comment dialog is not displayed at all. Two solutions

1. make the comment optional
2. do not display it at all

Additional context
We implemented the second solution in our branch long time ago: assistify@ab98c85