When you configure a group like this:
Follow-up possible: do not reopen ticket but create new ticket
Then Zammad will automatically put customer replies to closed tickets into a new ticket. This is a useful feature because some customers like to reply to ancient tickets instead of just writing a new mail, and this ensures that when enough time has passed, the new mail will become a new ticket.
But there are possibly situations where it might be counterproductive (e.g. an agent has accidentally closed a ticket instead of setting it to ‘pending close’, or the timeout for ‘pending close’ was too short, or the customer just took far too long to reply).
For these cases it might be very useful IMO when Zammad would automatically link the old and the new ticket, which it currently doesn’t do. Maybe even with a specific relation for that purpose, e.g. precedes/follows?