Unfortunately, somehow my setting for "sent" e-mails got changed so that TB only kept the last few months - acktually I want to keep them "forever" (until I delete them). I have various profile backups - is there a way that I could just import the "sent" items/folder? I guess importing "normally" (https://support.mozilla.org/en-US/kb/thunderbird-import) would probably just result in populating the inbox with messages that I already deleted in the meantime.