Recently SmartThings adding Lighting Groups devices. Basically you can add a number of lights to Lighting Group and then control state, dimmer, color, and other settings as 1 device. This would be super useful device type to support in ActionTiles.
At this time the Lighting groups are not part of SmartThings official API. There are hacky ways of sorta getting it to work, but they may chose to change it.
We will be able to add this useful feature when they finalize the API.
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