async fn fetch_folder(
session: &mut Imap,
account: &Account,
folder: &Folder,
full: bool,
) -> Result<Report, SyncError>Expand description
Fetches a folder’s new messages into its Maildir, then (full) brings
back what changed there on the server and older mail. One fetch at a time
per account, across processes too (the window and sioul sync):
otherwise both would see the same new UIDs and write each message twice.