Light groups of light groups

Configuration
1

I have a light.yaml with a bunch of light groups.

Most work fine, but I also have some that are various mixes of others. And some of the entities to include here would themselves be light groups defined in light.yaml

And these don’t work. Is it not permitted to use a light group as an entity in a new light group?

I know that you can manage it from the UI now, but I already have a pretty complex collection of groups in the yaml, so until there’s an auto-convert, I want to stick with the yaml file.

example 
# This one would work
- platform: group
  name: outdoor_front
  entities:
    - light.garage
    - light.front_door

# This one would work
- platform: group
  name: outdoor_back
  entities:
    - light.shed
    - light.terrace 

# This one would NOT work
- platform: group
  name: outdoor_all
  entities:
    - light.outdoor_front
    - light.outdoor_back