Feature Request Summary: 

Currently if you unshare a ticket, it does not show that change in the list of changes in ticket event history. You can tell it was unshared at some point, as there's an event when it was shared in the past, and the ticket will be unshared now. It would be helpful for that to be a specifically logged change when troubleshooting ticket sharing issues.

Description/Use Cases: 

As a Zendesk admin, I want to see when a ticket was unshared as part of its ticket history so that I can identify problems with a ticket's journey.

Business impact of limitation or missing feature:

This is low impact for us - it can make it harder or more time-consuming to look at histories of shared tickets, but that's not a frequent task.