Hue Brightness Channel/Slider

I’ve got hue-lights which seem to have different channels and behave differently when using sliders.
One (a mobile lamp) has a brightness channel and when using a slider, it shows the brightness value - just as it should:

The other one (floor lamp) doesn’t have a brightness channel in its thing-definition:

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When controlling it with a slider, the lights work as the should. But at the same time, the slider shows “NULL” instead of the brightness-number:

How can I get OH to show the correct number? - and if that’s not possible, is there a way that at least nothing (neither a number nor null) is shown?

The other problem is that I want to change the brightness with a rule (if motion detectors is changed and time is between 6 and 8 then set brightness to 80; I’ve done this in node red, but the value setting doesn’t work so well because of the missing brightness-channel)