No closing parent before all sub tickets

Hello,

as it stands right now parent-tickets can be closed before all sub-tickets are closed.
I am sure this is intended behaviour and most definitely how many people expect it to behave.

That is why we are looking for a toggle which changes said behaviour to "P-ticket can only be closed after all s-tickets are closed."

Seeing as this probably leads to issues/confusion where someone would want to add s-tickets to an already closed p-ticket, at least a toggle for a warning akin to "Ticket has unresolved s-tickets. Are you sure you want to close it?" would be very appreciated.