Lack of interest Allow self-signed SMTP/TLS certificates with your chosen email server.

[glitch77]

Would it be possible to add a tickbox to later Xen versions that allows you to use self-signed SMTP/TLS certificates with your chosen email server? ProtonMail Bridge (https://protonmail.com/bridge/) and requires this to function, but I'm sure many other relays would benefit. The code is simple, just need to add some options to ...\swiftmailer\lib\classes\Swift\Transport\StreamBuffer.php;

Change: $options = array();

To: $options = array('ssl' => array('allow_self_signed' => true, 'verify_peer' => false));

It would also need to be added to the IMAP Zend mailer as well.

 

[Kirby]

Hmm, not valdating peers is generally frowned upon and thus strongly not recommended.
I am not familiar with ProntonMail, but can't you just configure it to use an official certificate like LetsEncrypt?
This would solve the issue.

 

[glitch77]

The bridge runs locally and only listens on 127.0.0.1 with a non-replaceable self-signed cert.