HappyFox allows Agents to delete attachments linked to a ticket update.
To delete an attachment, hover over it and click the "Trash Bin" Icon.
The deletion process is non-reversible and hence must be exercised with caution.
Deleting ticket attachments is governed by a ticket-level permission "Delete Attachments". If you are not able to see the "Trash Bin" icon, then contact your helpdesk administrator.