ProtonVPN’s no-logs policy certified by an external audit
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Even that claim is false; they keep an escrow key that all of your browser keys are derived from anyway since you there isn't any way to bring your own key.
...not to mention that any government agency can just ask to listen to the SMTP server -- who cares if it's encrypted afterwards when they grab it off the line?
As for the escrow key, I didn't know. Is it a signing key? Because that makes sense. Otherwise, do you have a reference? Could have sworn this was tested of them in court.