I have a Microsoft Online Exchange email account configured in Thunderbird 142.0 as an exchange account (not IMAP). I had a draft email in the drafts folder that was created using Outlook Web Access (OWA). Upon saving the email in Thunderbird, the email completely disappeared from the drafts folder. This email was not found in trash, sent items, outbox or anywhere else. Further if I create a new email message and click save or save as draft it appears momentarily in the drafts folder then completely disappears and cannot be found. In Account Settings > [Exchange Email Account] > Copies & Folders > Drafts & Templates > Keep draft messages in: I have "Drafts" Folder on: [Exchange Email Account] set. If I change this to Local Folders, the draft message does not get lost (but also does not sync in exchange). I also have a Gmail account in Thunderbird which does not exhibit this behavior of losing drafts. This is a fresh installation of Thunderbird.