Hass.io MQTT addon Can't see any devices

Hello alltogether,

I have been running home assistant for quite some time now and so far it’s working great!
However, a week ago I bought a xiaomi roborock (gen 1) and I can’t get it to play nice with HA.
I don’t have any other MQTT devices, so I started by installing the MQTT core addon. I followed the instructions and created a user “mosquitto” with a password and admin privileges. I also added the integration on the integrations page.
Until now, I configured Home Assistant solely by adding entries to configuration.yaml and lovelace-ui.yaml, so I’m a bit lost. Here is the log of the addon:

[18:14:16] INFO: Setup mosquitto configuration
[18:14:16] INFO: No local user available
[18:14:16] INFO: Initialize Hass.io Add-on services
[18:14:16] INFO: Initialize Home Assistant discovery
[18:14:16] INFO: Start Mosquitto daemon
1580490856: mosquitto version 1.6.3 starting
1580490856: Config loaded from /etc/mosquitto.conf.
1580490856: Loading plugin: /usr/share/mosquitto/auth-plug.so
1580490856: |-- *** auth-plug: startup
1580490856:  ├── Username/password checking enabled.
1580490856:  ├── TLS-PSK checking enabled.
1580490856:  └── Extended authentication not enabled.
1580490856: Opening ipv4 listen socket on port 1883.
1580490856: Opening ipv6 listen socket on port 1883.
1580490856: Opening websockets listen socket on port 1884.
1580490856: Opening ipv4 listen socket on port 8883.
1580490856: Opening ipv6 listen socket on port 8883.
1580490856: Opening websockets listen socket on port 8884.
1580490856: Warning: Mosquitto should not be run as root/administrator.
1580490857: New connection from 192.168.51.33 on port 1883.
[INFO] found mosquitto on Home Assistant
1580490858: New client connected from 192.168.51.33 as mqttjs_e011e07a (p2, c1, k60, u'mosquitto').

As far as I can see, the roborock connects to the mosquitto broker, but on the integrations page, it only says “this integration has no devices”
So… What am I doing wrong?

OK… I have no idea what I did different this time from the past 100 times, but it is working now…