I am not sure whether this question should be classified under "Email and messaging" or "Settings" but here goes. I am getting a lot of emails from people and organizations that I would rather not open and look at or am bothered to do so. And setting up filters for each and every email sender would clutter up the workings of Thunderbird creating a significant lag during startup and mail download (am using IMAP). Is it possible to have a sender or organization set up in the message filter which then during the next go-around returns the email to sender with a subject line saying "Returned to sender, no such address"? Thanks for any consideration of this request. James