Docker - What’s included?

Just started with docker running on OpenMediaVault so the docker image not hass.io. I’ve moved my config over from my RaspberryPi and things like nmap are working ok but I just wonder what other integrations are included with the Docker image?

Eg MQTT?

As with most sensible docker images, it only contains one program - HomeAssistant. This does include its own embedded MQTT broker, but that is limited in features. If you want to use an external MQTT broker, you need to run a separate docker image for that, such as the official mosquitto image.