Shader Graph Matrix4x4 Convert to Property

Newbie question here, but something seems like a bug. I spent a long time trying to figure this out, thinking my math is wrong.

1. Create a Universal Render Pipeline project, set Project Settings | Graphics to URP, etc.

2. Create a new Shader Graph and a New Material with that shader, and assign to a new Sphere

3. Create a graph where a Vector4(1,1,1,0) and a Matrix4x4 (0.5 scaling matrix) are plugged into a Multiply, and set the result to Color(3) of the master

As expected, my sphere turns gray. All good and expected.

Now, right click on the Matrix 4x4 node and Convert to Property, then Save Asset.

The sphere now turns to white! What happened??