CIRCLE WITH A DOT

@jwildeboer any information about what we need to do to keep our email server communicating?
At present I use my letsencrypt certificate.

@Linux_in_a_Bit @markuswerle just to clarify, which display manager are you using? It's the display manager where you configure this (or accept whatever is the default). You have a choice of display manager if you use Debian (or most other linux distributions for that matter). I use Cinnamon, others use Gnome or KDE or XFCE or other alternatives.
So you have choices. In this respect desktop Linux is to the Windows or Apple desktops much like the #Fediverse is to Facebook or X. But yes it can be confusing.

@markuswerle @Linux_in_a_Bit actually you can do these things in Debian Linux e.g I have a separate button on my top bar to access quit, restart, suspend, hibernate, using sudoers although these days suspend doesn't properly any more, but hibernate still does, but it was very much up to me as the user to set this up myself or to find a Debian variant that already does exactly what I wanted.
When I used Mint it mostly worked out of the box so I could recommend it to newbies, whilst remaining configurable, but then it got the systemd cancer so now I use Devuan.