There are a few mail messages which show up in my mailbox but are completely blank. I can read these messages on my iPhone and Gmail on the web so I know they are on the server.
Geoff's 16" 2019 MacBook Pro
Safe Boot from the HD, (holding Shift key down at startup), does the problem occur in Safe Mode?
Safe mode attempts to repair Disks & clears lots of caches, so if Safe Mode works try again in regular boot.
If you have no POP accounts & they’re all IMAP accounts then in Mail’s Mailbox menu choose Rebuild.
Empty Mail Messages which I can see on my iPhone and Gmail web app
