I have my own domains and when I email businesses and organisations I always give them a unique email address like: thunderbird.support@jhnospam.co.uk. This helps reduce SPAM and identifies when organisations are hacked so I can 'kill' individual addresses with my domain registrar. I currently achieve this using a 'generic' NOSPAM Thunderbird account with a temporary 'from' address (which I need to change occasionally and 'kill' with my domain registrar to prevent SPAM) and I edit the 'reply-to' address when I send an email to such an organisation. This tends to work OK most of the time but often the 'reply-to' address gets lost at the other end, possibly when emails are forwarded internally. This can leave some emails sent to old temporary 'from' addresses never reaching me. Much neater would be to send such emails with identical (and unique) 'from' and 'reply-to' fields. Has anyone any ideas how to achieve this but obviously without creating an individual account each time? If Thunderbird allowed the editing of the 'from' address, perhaps under special circumstances, this would be a solution.