Shelly configuration/settings | UI vs configuration.yaml

I’m building a new HA instance. I installed HACS (and saw the shelly folder created in custom_components as per the doc), installed the Shelly integration on HACS and then the Shelly integration via Home Assistant integrations. In line with the general trend I try to minimise changes to configuration.yaml.

When I open Settings in the HA integrations page I get a message that

Your settings for ShellyForHass is stored in config.yaml and can't be changed here.

You can convert this instance to an integration stored in the database. If you do this you can change the settings here and settings in config.yaml will be ignored and you can remove them.

There’s nothing about shelly in configuration.yaml (I assume that config.yaml per the above message refers to configuration.yaml).

Why do I get this message?