Fixed formatting on partial nodes

editor/js/tools/menus/selectmenu.js

@@ -185,7 +185,7 @@ export class SelectMenu extends ToolMenu {
             var value = node[propertyKey];
 
             var formattedValue = undefined;
-            if (propertyKey === Graph.NODE_REFERENCES) {
+            if (propertyKey === Graph.NODE_REFERENCES && Array.isArray(value)) {
                 formattedValue = value.join("\n");
             } else {
                 formattedValue = value;