I belong to a listserv that sends me copies of messages I send to the list address. When I delete the messages from my inbox, GMail also deletes the message from my sent folder. I'm aware that the whole deal with GMail and tagging is that you only have one copy of a message and if you delete it from one place it's gone. However, it doesn't seem like that should be the case with Sent mail.
Is there any setting or add-in I can use that will prevent emails I delete from other tags from being deleted from the Sent messages?
(I use both the GMail web client and Thunderbird; solutions for either one are welcome.)