No shadow with world position offset + unlit

I have an unlit material using world position offset that casts no shadow when it should cast one.
I have shadows with unlit without WPO, lit with WPO, but not with unlit+WPO.

Unlit shading model disables shadowcasting.

Unlit materials by definition do not interact with light, so they don’t cast shadows. However you can usually get what you want by using a lit material, setting BaseColor and Specular to 0, then just keep your EmissiveColor input.

As I said in the question, I have shadows with unlit materials. The shadows disappear when I use World Position Offset.

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