Is it possible to tell discourse to notify about new update being available but outside of webui?
Perhaps sending an email or even better by using filesystem - touching/spitting out a customized file to a given location. When local installation itself, finds that such update is ready - not outside of this local discourse and by going out to git or any other, external source code repo.
If you have SMTP configured, and you’ve configured a ‘contact email’ in the site settings, then you should receive an email notification for new versions: