I’m running Feren OS 2021.07. I successively installed ProtonMail Bridge and signed in using my ProtonMail account. When I try to add my ProtonMail account to Mailspring, using the settings provided by the ProtonMail Bridge for my account, I receive a “Certificate Error (SMTP)”. The verification error log reports:
OpenSSL version: OpenSSL 1.1.0f 25 May 2017
Verification failed:
X509 verify_cert_error_string:
self signed certificate
X509_get_subject_name
QUIT
My system stores certificates at:
/etc/ssl/certs/ca-certificates.crt