Seems like refraction doesn’t work if material layer is connected in the final material via “Use Material Attributes”. To make it work the layer needs to be broken to material attributes, material has to have unchecked “Use Material Attributes” and all attributes that are used in the layer manually connected to the final material.
Hi Tomas,
What attributes/nodes are you using in the GlassLayerTest node? Knowing what that node does will help me to better assist you.
-Adam
The glass layer is using the following attributes:
- BaseColor
- Metallic
- Specular
- Roughness
- Opacity
- Normal
- Refraction
edit: wanted to make that a nice list, but somehow the edit doesn’t want to save the list 
Hi Tomas,
I was able to reproduce your bug and have placed a bug report in for it. Thank you for bringing this to our attention!
-Adam
Hey,
Just want to report this bug is still present in 4.10.1. Its been nearly 2 years so figured I would re-report it.
Refraction does not work when material uses [true] use material attribute.
I had a unlit translucent material using emmisive, opacity, and refraction. Breaking the material function and plugging in works.
Hi Daniel,
Please open a new post in the Bug Reports section so we can get this tracked properly. This is an old, archived post from our beta users, and enough has changed since then that I’d like to get fresh eyes on it. Include as much information as you can. I’ll get someone assigned to investigate and we’ll go from there. Thanks!