Why in Thunderbird or in any other known email client software, do I have to create a new email using "forward" or copy-paste, in order to resend an email that for some reason, like the destination server mail was down, did not reach the destination and has to be resend again? Why not create an option or a button for "resend", that just repeats the email and sends it again to the destination email addresses? It seems a basic option that should exist in every email client software, but unfortunately it does not exist.