Vertex shader unable to use TEXCOORD1 / models secondary uv map

[DeltaDesigns]

Describe the bug

When I try to use a models secondary uvs for a detail texture in my shader, the texcoord returns nothing, just black. texcoord0 and color0 work as intended but anything else wont. Also, the texcoords appear fine in ModelDoc

To Reproduce

1. Use the provided shader and model
2. Make a new material for model using the shader
3. Shader should be showing the models texcoord1 as its albedo, but wont

Expected behavior

TEXCOORD1 and 2 and whatever else the model may have, should be available to the vertex shader to use

Media/Files

Viewing as albedo:

Viewing in Stream Visualization:

texcoord1test.zip

Additional context

No response

[DoctorGurke]

I noticed this option recently, have you tried enabling the "Secondary Uv" option on a shader like complex?