diff --git a/Userland/Libraries/LibJS/Heap/HeapBlock.h b/Userland/Libraries/LibJS/Heap/HeapBlock.h
index 595e78f5c3..ffa42b174c 100644
--- a/Userland/Libraries/LibJS/Heap/HeapBlock.h
+++ b/Userland/Libraries/LibJS/Heap/HeapBlock.h
@@ -111,7 +111,7 @@ private:
     size_t m_cell_size { 0 };
     size_t m_next_lazy_freelist_index { 0 };
     GCPtr<FreelistEntry> m_freelist;
-    alignas(Cell) u8 m_storage[];
+    alignas(__BIGGEST_ALIGNMENT__) u8 m_storage[];
 
 public:
     static constexpr size_t min_possible_cell_size = sizeof(FreelistEntry);