net11.0 
namespace System.Drawing.Imaging.Effects
{
    public sealed class GrayScaleEffect : ColorMatrixEffect
    {
        public GrayScaleEffect();
    }
}
.NET
9.010.011.0
Information specific to net11.0
Assemblies

System.Drawing.Common , Version=11.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51

System.Drawing.Common , Version=10.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51

Referencing

Your project needs a package reference to System.Drawing.Common.

Package System.Drawing.Common (11.0.0-preview.2.26159.112) net11.0
Platform Restrictions

This API is only supported on the following platforms:

  • Windows >= 6.1
  • Built-in API
  • Package-provided API