The facades for the System.Drawing.[Common/Primitives] assemblies placed types like Color/SystemColors in the wrong assembly. In turn libraries linked against these facades expect the types to exist in System.Drawing.Common. This breaks once the libraries are used in the .NET 6 context.

I recently workarounded that on Xamarin.Forms iOS build but hit it again with Xamarin.Essentials. It should be fixed here once and for all.