diff --git a/addons/material_maker/graph_edit.gd b/addons/material_maker/graph_edit.gd
index d694a7c..a8d5360 100644
--- a/addons/material_maker/graph_edit.gd
+++ b/addons/material_maker/graph_edit.gd
@@ -303,5 +303,10 @@ func _on_ButtonShowTree_pressed() -> void:
 	var graph_tree : Popup = preload("res://addons/material_maker/widgets/graph_tree/graph_tree.tscn").instance()
 	graph_tree.init("Top", top_generator)
 	add_child(graph_tree)
-	graph_tree.connect("item_double_clicked", self, "update_view")
+	graph_tree.connect("item_double_clicked", self, "edit_subgraph")
 	graph_tree.popup_centered()
+
+func edit_subgraph(g : MMGenGraph) -> void:
+	if !g.is_editable():
+		g.toggle_editable()
+	update_view(g)
diff --git a/addons/material_maker/widgets/graph_tree/graph_tree.gd b/addons/material_maker/widgets/graph_tree/graph_tree.gd
index 714e7c9..a74d8ca 100644
--- a/addons/material_maker/widgets/graph_tree/graph_tree.gd
+++ b/addons/material_maker/widgets/graph_tree/graph_tree.gd
@@ -7,6 +7,7 @@ func init(graph_name : String, generator : MMGenGraph) -> void:
 	$Tree.clear()
 	var root : TreeItem = $Tree.create_item(null)
 	root.set_text(0, graph_name)
+	root.set_custom_color(0, Color(1, 1, 1))
 	root.set_metadata(0, generator)
 	fill_item(root, generator)
 
@@ -15,6 +16,8 @@ func fill_item(parent : TreeItem, generator : MMGenGraph) -> void:
 		if c is MMGenGraph:
 			var item : TreeItem = $Tree.create_item(parent)
 			item.set_text(0, c.get_type_name())
+			if c.is_editable():
+				item.set_custom_color(0, Color(1, 1, 1))
 			item.set_metadata(0, c)
 			fill_item(item, c)