I think I’ve got this right. If I’m wrong, I’m about ready to throw something.
I believe I’ve been using HassIO with the Mosquitto plugin. I can’t afford to keep replacing SD cards, so I dug out an old netbook, installed Mint Linux (it’s what I had and it’s nearly Ubuntu). Install HA and it seems to be working.
But, now I have HA and not HassIO. So, I have no Mosquitto.
There are instructions for MQTT on HA. MQTT appears to be built into HA. Why is Mosquitto an option in HassIO?
Is it possible to install any of the HassIO components now that I’m HA? It was really useful having the web based config editor.