Remove php-gpg, add openpgp-php and phpseclib. Add template file for settings. Add "send test" functionality. Add messages.po
Secure Mail
Send notification mails to user encrypted with GPG. Each user can enable it and submit his public key under Settings-> Addon -> "Secure Mail" Settings.
Use 'openpgp-php' library, a pure PHP implementation of GPG/PGP. See project repo.
Need Friendica version > 3.3.2 to work.