Do a turboprop’s compressor and turbine rotors windmill when the engine is shut down and feathered? If a jet engine is shut down in flight, it continues to turn due to the aircraft’s forward motion forcing air through the engine, causing it to “windmill” in the airflow.

Is this also true for turboprops?  When a turboprop engine is shut down and its propeller feathered, do its compressor and turbine rotors keep windmilling in the aircraft’s slipstream, or do turboprops have some way of closing off their engine intakes to prevent this when the engine is shut down?
A feathered propeller is designed not to windmill in flight, however in the case of a power turbine or even a propeller connected to both the compressor and turbine, it's far easier to turn than an old radial when in the feathered position. 

Nothing physically stops the propeller from turning when feathered beyond the force required to turn the power turbine/gearing or whatever the propeller is connected to and the air hitting it at the right angle. Straight airflow shouldn't turn it, however any flow from the sides would turn a feathered turboprop. Unlike a turbofan, the propeller changes pitch so the air affects it differently.