To get to see the mail server version currently executing, the only way is to grep the right log line just after starting it. Still haven’t found the UI application’s version anywhere. It would be really useful to have both these version numbers somewhere in the WebUI.
As of 1.0.6 the WebUI version is now visible by hovering the logo.
The developer has stated the server version will never be available from the WebUI https://support.stalw.art/t/version-of-stalwart-in-ui/759
They could add it via an admin-authenticated endpoint, which will still hide it from the public but allow it to show in the WebUI