Tangent Vector is a Vector3 but should be a Vector4

Unity Engine
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I’m trying to convert one of my custom shaders to ShaderGraph and was surprised to only get a float3 from a Tangent Vector node. In GLSL the TANGENT semantics are float4, so in the graph I have no way of accessing tangent.w.

Probably this isn’t an issue for most people but this shader works with meshes I build myself too, and I actually encode information in the tangent semantics that aren’t tangents at all. They’re just 4 values that I think go together and so I abused the mesh’s tangents to store them. It’s easy to work around and just use 2 UVs instead or something similar, but still, I would expect the Tangent Vector node to give me access to all 4 channels of the TANGENT semantics.

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We are using vertex color for similar usecase.

I guess you might run into problems if you override tangent for other purposes when you also use normal mapping.