If you wish to include some information about the ticket in the update emails here's how you do it.
Go to: Settings > Company > Emails > Plugin Emails > Ticket Updated
Then add this in the content boxes:
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Ticket ID: #{ticket.code}
Priority: {ticket.priority}
Status: {ticket.status}
Last reply: {ticket.reply_by}
Opened: {ticket.date_added}
Ticket URL: {update_ticket_url}
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