This may or may not be an issue. My understanding is that using the # with a hex color in MQTT payload should set the colors of the lights leaving all other settings as is. Where * with a hex color in the payload would set the color and light the lights. If my understanding is correct the "Websocket API" page should state that using # would change the state from OFF to ON. Otherwise, I would prefer to just change the color and not change the state:)

The issue is that the "state" changes from OFF to ON when you change the color using #. Let me know if this is expected.

Here is the initial config of my lights.
"{"state":"OFF","color":{"r":236,"g":33,"b":196},"brightness":245,"color_temp":327,"speed":33,"effect":"Fire Flicker"}"

I change the color using this command as the payload.
#28f31a

Now the HA config of my lights is.
"{"state":"ON","color":{"r":40,"g":243,"b":26},"brightness":245,"color_temp":327,"speed":33,"effect":"Fire Flicker"}"