murmelade

Their privacy policy expressly states they have access to metadata and they have a non-public blacklist which filters “undesirable” domains. Try creating an account on zlibrary using your Protonmail.

Also worthy of notice, they are legally forced to hand over shitloads of user data as seen in their transparency report.

Not to be a tinfoil hat guy, there’s good reason for this and there’s no free email service that is much better privacy-wise. The actual content of your mails are probably safe with Proton.

I deleted my Protonmail after learning about their metadata filtering practices. The more you learn about Proton the sketchier they seem.