
Can one undelete an old message that's been accidentally deleted?
I wanted to reply to an old (1 year +) message and thought that I was editing the reply rather than the original message. When I highlighted a section of the message I wanted to delete and hit "Delete", Thunderbird instead deleted the whole message, apparently irretrievably! It's not in Trash, and clicking Undo undoes the deletion of other messages, but not the one I just accidentally deleted.
I tried this deliberately on another old message, with the same result. Doing the same thing on a newer message puts the message in Trash, as expected. I have "Don't delete any messages" checked on the Local Disk Space setting.
Why (apparently) do old messages not go to Trash when deleted? Is there any way of recovering a message deleted in this fashion?