I have sonoff mini using tasmota 8.3.1 (lite) and SetOption19 1; HA 0.111.1, Hass 227 and Mosquitto Broker 5.1 addon. I have MQTT itegration working with dicovery on. I can send MQTT request to the sonoff and works, But MQTT integrantion can´t find sonoff in auto discovery. I already try SetOption30 on and off. Reboot everything several times. Maybe is a bug, but is my first configuration.
Try option 19 to on
Will never work. Tasmota lite does not support discovery. You have to upgrade your sonoff mini to tasmota.bin.
In the tasmota web-interface, choose firmware upgrade
In ota url, enter
http://thehackbox.org/tasmota/release/tasmota.bin
when it is finished, enter setoption19 1 again in the tasmota console.
Tasmota lite is required when you do an upgrade from the sonoff software, but once tasmota is installed, you can update to the full tasmota 