As an example, I might order a flashlight from a vendor. I would have received an order confirmation by email, and then might get another message when it is delivered. But depending on the vendor's practices, these messages might not say "flashlight." A year later, suppose I want to know where I ordered the flashlight. If the messages refer to an order number but do not say "flashlight", I don't have a simple way to find this out. What I would like to do, when I archive the message (or subsequently), is to edit the body (or subject) to include this keyword. Is there any straightforward way to do this in Thunderbird? Thanks for any advice.