Broken displacement mapping with groups

[tim_harding]

If I have a displacement map in the same material mask as a group set to Add or a group that contains a Group Mask, displacement mapping loses its effect on refractions.

[vladimir.nedev]

Can you send me a scene or attach a screen-shot of your shader tree ?

Greetings,
Vladimir Nedev

[tim_harding]

Here, I've uploaded a scene file with renderings of what happens with the groups turned on and off: https://www.dropbox.com/sh/8416jl46z...hmK_plhga?dl=0

Cheers!