very strange problem:
A SpeedTree model comes with vertex colors for shading control. These vertex colors show up in Shaded Mode / EEVEE Render, but disappear when switching to Cycles. They are neither rendered in color, nor are they being used in my shader which I made for color variation.
This is a consistent problem with 2.83 and 2.90.1.
Is this a bug or am I doing something wrong?
I also attached the file below, maybe something is off there?