Has there been any movement with a checklist feature? It would be a huge improvement to Zammad.
Another, perhaps simpler request, would be to have an editable pinned note or similar that you could use to quickly summarize the status of a ticket, notes about things to be done, etc. When a ticket gets long, it is easy to miss customer direction or decisions that were made throughout the ticket conversation history.
Please add these features to Zammad!