diff --git a/desktop/plugins/public/ui-debugger/components/Visualization2D.tsx b/desktop/plugins/public/ui-debugger/components/Visualization2D.tsx
index dfb13db5e..3bdf6ecc4 100644
--- a/desktop/plugins/public/ui-debugger/components/Visualization2D.tsx
+++ b/desktop/plugins/public/ui-debugger/components/Visualization2D.tsx
@@ -194,7 +194,11 @@ function Visualization2DNode({
 
   //if there is an active child don't draw the other children
   //this means we don't draw overlapping activities / tabs etc
-  if (node.activeChildIdx && node.activeChildIdx < node.children.length) {
+  if (
+    node.activeChildIdx != null &&
+    node.activeChildIdx >= 0 &&
+    node.activeChildIdx < node.children.length
+  ) {
     nestedChildren = [node.children[node.activeChildIdx]];
   } else {
     nestedChildren = node.children;