Other service calls accept any kind of target, like areas, devices, or the new labels. But this specific service call returns an error Failed to call service homeassistant.update_entity. extra keys not allowed @ data['label_id']. Got None when trying to use other targets, even when they include several entities, and they exist.
Other calls accept those wrappers as targets, I imagine all calls should. After all they’re just that, wrappers to be convenient. If they can’t be used it defeats the purpose.
That’s what I mean. UI seems to be generic and show any target for just any service, even if not supported. But I think they all should be, since they’re just ways of wrapping entities in the end.