[dev] Set ticket cannot be edited after close

Hi all, One of the requirement in my workplace is that a ticket cannot be edited (add note or decision) after the ticket is closed. I have two questions: 1. It seems that the default setting is that we can add note and decision even if the ticket is already closed. How can I change this setting? If there is no setting about this, I think I have to change the code a little bit, fyuhh.. It would be tiresome :p. 2. Another requirement is that if we want to add note or decision, the ticket should be opened first. How can we achieve this without making any code changes? Thank you before. Ikhsan