i have object and environment sphere

i've added Refraction Mask property to my object and cleared it so i expect that nothing will refract in this object

then i put glass shader from material palette on it, set reflection, specular to 0 so the only thing i should get are refractions
and since refraction mask on the object is empty I expect black render

but the refractions of the environment sphere are visible in the object
only when i clear reflection mask field i get black render

can this be logically explained? are both refraction and reflection rays labeled as reflection? or am I missing something obvious?

one solution i can think of is custom VEX shader with object scope for refractions, but that's my last option

Does anybody here have experience with Refraction Mask?

H 10.0.608

it might be the total internal reflection which reflect the env. I am not sure though.

How about try a thin sheet and see if it refract the objects behind it?

i tried it with plain grid
it doesn't wok

seems like reflection mask controls both (refl/refr)
i wanted to use it with PBR since i've read in journals that it supports reflection/light/shadow masks, but refraction mask behaves the same way

It seems, i have to stick with non-PBR renders and custom VEX shader

can anyone confirm that the reflection mask isn't working?
should I submit it as a bug?