You are running an unsupported installation --> what are the consequences exactly?

I have been running HA with supervisor on Ubuntu server without a problem for 6 months. Now I realised in the settings section that apparently

You are running an unsupported installation

Well… unsupported in what sense? it doesn’t tell on Operating System - Home Assistant

and HA seem to work just fine

In the sense that you can only expect community support and the developers will not respond to any issues you may create in future.

Until it doesn’t, as several users discovered last December (including me).

In addition to the “unsupported” message, an additional “unhealthy” message appeared. In my case, I was using Ubuntu 18.05 and Supervisor considered the installed version of Network Manager to be out of date (with no upgrade path). While in the “unhealthy” state, Supervisor disallowed upgrading Home Assistant and creating snapshots. The quick fix was to upgrade to Ubuntu 20.04 (which has an updated version of Network Manager).

All of this happened immediately after a Supervisor upgrade (which cannot be suppressed) and shortly before the Christmas holidays (when fixing one’s broken instance of Home Assistant isn’t a welcome task). After the holidays, I switched to the officially-supported Debian 10.