Color Temperatur for Tradfri Groups


I have a lamp with two tradfri bulbs. In the Tradfri Gateway I created a group called office lamp with these two bulbs inside. In Home Assistant i have now this group as a light entity, light.office_lamp. But with this entity it is not possible to change the white color of the two bulbs within this group. Only changing the brightness is possible.

Would be nice, to have this possibility too, that it is possible to change the color for the group und therfore for the bulbs within this group.

Thanks and regards

Looks similar to this one Ikea Tradfri: Transition and Moods