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Proton Mail Discloses User Data Leading to Arrest in Spain
(restoreprivacy.com)
This is a most excellent place for technology news and articles.
...yes, that's what I said. But sign them locally. Do not put your private key on Protons service. Sign and distribute pub keys locally.
Probably should have clarified.
Also, paid IMAP/SMTP makes Proton a freemium service. Thought I should just underline that.