not sure if it's a bug or I'm doing something wrong but when I export any Subtool with Polypaint using FBX it will set the color of vertex ID 0 to all other vertices. it still exports as expected using OBJ.
this happens on all meshes whether it's Dynamesh, Zremesh, with and without UVs.
the red is vertex ID 0:
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the export settings:
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in Maya:
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Arnold render:
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Marmoset viewport:
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