How did you redirect these messages?

I just used the "redirect" button which is available whenever I am viewing my folders whilst connected. I resent them to one or two recipients.

Thunderbird doesn't have a native Redirect function. Are you using an add-on such as this one?

https://addons.mozilla.org/en-US/thunderbird/addon/mailredirect/

Mine is broken; it says it's compatible up to v42 and I'm trialling v47.

I'd hope it leaves a copy in the Sent folder…?

Edit: I just found the "developer channel" version 0.8.8a2 and it's working again. Mine left a copy in the Sent folder.

I'm using add on Mail Redirect 0.8.7. It doesn't leave a copy in the sent box it has the option to resend to the sending address. I had disabled this which is probably why I had the problem in the first place. I'll ensure it is enabled in future.

Mail Redirect only leaves a copy in the Sent folder when you configure it to do so. Go to Tools -> Add-ons Manager -> Mail Redirect -> Options and check 'Place copy of redirected mail in Sent folder?' This only works when you also have configured Thunderbird itself to save copies of sent messages…