Unit of thermal properties

The thermal_properties.yaml claims in the header line all units are per unit cell (natom). Then, all values are given in something / mol.

This is slightly confusing, are all properties given now per mol (so formula unit / avocado-constant) or referenced in some way to the unit cell volume?

I'm explicitly asking because I want to compare thermal stabilities of systems with different unit cell sizes.

PS: Applies to zero-point energy as well. This one also seems to be in kJ/mol.