How to Configure TLS Client Certificate Authentication for IMAP & SMTP in macOS Mail app — Step‑by‑Step Video Guide (opens in new tab)

The Mail app on macOS ships with more features than any other OS, including support for S/MIME and the TLS client certificate authentication method for both IMAP and SMTP. As far as I know, it isn't fully supported by any client other than the open-source Claws Mail client for