In Mail, the links between the List Preview entry and the actual message have broken
In Mail, the List Preview entry no longer links to the actual email message identified. Not with every email, but with some. Click the Preview list entry and a different email message opens. Cannot restore the original email, even from Archive. Problem may have arisen when the email account was ported to a new laptop. It does not always happen with recent emails, but with older ones.
MacBook Air 13″, macOS 10.15