SetRTSpecialHeaders

Hi everyone
I have a question about SetRTSpecialHeaders => RT::Action::SendEmail - RT 4.4.4 Documentation - Best Practical

What is the usage of each of the following header:

X-RT-Loop-Prevention
X-RT-Ticket
X-Managed-by
X-RT-Originator

And if they are disabled in the SendEmail.pm, what happens…??