diff --git a/src/Tree.tsx b/src/Tree.tsx
index 9529601..d24d149 100644
--- a/src/Tree.tsx
+++ b/src/Tree.tsx
@@ -286,7 +286,7 @@ const generateNewTree = <
   let tempRecord: NodeRecord<TNodePublicState> | null = rootRecord;
 
   const useIdleCallback =
-    'requestIdleCallback' in window &&
+    typeof requestIdleCallback !== 'undefined'
     placeholder !== undefined &&
     // If placeholder is set to null and this is the first build, idle callback
     // won't be used. It is necessary for trees with async data which can be