Is ProtonMail really encrypted?

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Tags

1. #mailbox
2. #allows
3. #people
4. #password
5. #email
6. #messages
7. #protonmail
8. #sending
9. #encrypted
10. #delivered
11. #providing
12. #unique
13. #generic
14. #instead
15. #message
16. #exactly
17. #decrypted
18. #recipient