use Sandbox.System.Editor here

Author: QuackCola

game/addons/tools/Code/ShaderGraph/SubgraphNode.cs

@@ -24,7 +24,7 @@ public sealed class SubgraphNode : ShaderNode, IErroringNode
 	[Hide]
 	public override IEnumerable<IPlugOut> Outputs => InternalOutputs;
 
-	[Editor( "subgraphnode" ), WideMode( HasLabel = false )]
+	[Sandbox.System.Editor( "subgraphnode" ), WideMode( HasLabel = false )]
 	public Dictionary<string, object> DefaultValues { get; set; } = new();
 
 	[JsonIgnore, Hide]