That means whatever software you are using on HE, to expose devices to Home Assistant via MQTT Discovery, is responsible for rounding the values (via how it defined the sensor’s configuration).
FWIW, I have numerous devices modeled as MQTT Sensors and their values are received, via MQTT Discovery, unadulterated by rounding or anything else (they aren’t coming from Hubitat).
See that first topic in your screenshot, the one that starts with the word homeassistant? Post its payload. That payload contains the sensor’s configuration.
There’s your answer as I had predicted. value_template contains a round(0). The developer of the application decided that the temperature value should be rounded.
You can either ask the developer to change that, or overwrite the topic’s payload, or manually configure an MQTT Sensor. The last two suggestions are impractical if you have many sensors.
Just a small addition. Indeed, the developer of HE app put round(0) right into the app code. Not sure why. But it was very easy to fix). Thank you again.
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