URP 2D light only illuminates sprites of the same colour

Here I have two basic sprites. One red, one blue. I also have a basic 2D light. As I move the colour wheel around, the light only illuminates the sprite with colour in the matching RGB channel. Ie it lights up the blue sprite when the light is blue, and the red one when the light is red.

What I expected is that the light illuminates both sprites, regardless of colour. If I set both sprites to white, the light illuminates them both. If it’s green, they are both dark. What gives?

I’d love to put the gif here but the page won’t let me

Figured it out.

Turns out this is actually exactly how physics works and I just did not realise. A red object will absorb all light except red, meaning it will appear dark under any light other than red. I was expecting different behaviour. Unity is performing as it should.

It’s not a bug, it’s a feature!