@girish Not on 2.3 - 2.2.1 still. I was VERY surprised that my email server became available after re-configuring Rainloop. That's the reason for "WTF" is my list of questions - makes no sense. I was unsuccessful connecting to my mail server from my phone for the whole day - was getting "Auth failed" errors (both from an Android app and Rainloop), so when I got to a computer I've tried it again with no luck. Re-configured Rainloop just for the hell of it and right after that was able to check mail from all my clients. I'll try to see if I can get any logs from docker at this point, not sure if I'll have that. What would be the way to re-start my mail server?docker restart mail should do the job, i hope?

@girish I've tried several, including connecting on the Nextcloud App Mail client as well as the SOGo App mail client. What convinced me this was an IMAP configuration issue was connecting to a different mail server and seeing that emails sent through it we're threaded by default, while emails sent through Cloudron's remained unthreaded and there existed no setting to change it.

Also, it is safe to disable encryption since the communication is internal to the VM.

Yep! I am on a Lightsail instance and simply needed to open up port 25 for traffic. Thanks!