src/pages/VisProgPage/visualProgrammingUI/components/DragDropSidebar.tsx

@@ -75,7 +75,9 @@ function addNode(nodeType: keyof typeof NodeTypes, position: XYPosition) {
     id: id,
     type: nodeType,
     position,
-    data: {...defaultData}
+    // Deep copy using JSON because thats how things work:
+    // Ref: https://developer.mozilla.org/en-US/docs/Glossary/Deep_copy
+    data: structuredClone(defaultData)
   }
   setNodes([...nodes, newNode]);
 }