"Your network preferences prevent content from loading privately" (Displayed in Apple Mail)

[jlc]

Hi!

On macOS Monterey (12.0.1), using the latest iCloud+ privacy features, namely Private Relay (Beta) for Safari and Mail Privacy Protection for Apple Mail, I've got for the first time an issue which seems to be related to Lockdown app.

Apple mail display on top of some emails "Your network preferences prevent content from loading privately.", without explanations nor logical reasons.

And when disabling lockdown's firewall, the content in the email is loaded fine (through Mail Privacy Protection), and the message does not appear anymore.

The issue happen to many email, such as Amazon's ones.

Is it known that Apple Mail Privacy Protection is interfering with Lockdown app (or vice-versa)?

Hope this help, please ask if you need more info!
As a side note, Lockdown is fantastic! Used it since many years, and it became a defacto app for ios and macos! Thanks for such an amazing work!

With best wishes,

Jean-Luc