SDK: Hide second dropdown in PF_ADD_LAYER

Hi

On a c++ effect, when I create a layer selector parameter with "PF_ADD_LAYER". I get the classic layer selector dropdown and the second dropdown with the options to chose "Source", "Masks" or "Effects & Masks".

My question is, can I hide the second dropdown? I only need the first where the layers is selected, so it feels a little odd and confusing to always include the second.

Thanks,

Jakob