diff --git a/fpdfsdk/pwl/cpwl_list_box.h b/fpdfsdk/pwl/cpwl_list_box.h
index 48b53e5..1e56697 100644
--- a/fpdfsdk/pwl/cpwl_list_box.h
+++ b/fpdfsdk/pwl/cpwl_list_box.h
@@ -97,8 +97,8 @@
  protected:
   bool m_bMouseDown = false;
   bool m_bHoverSel = false;
+  std::unique_ptr<CPWL_List_Notify> m_pListNotify;  // Must outlive |m_pList|.
   std::unique_ptr<CPWL_ListCtrl> m_pList;
-  std::unique_ptr<CPWL_List_Notify> m_pListNotify;
   UnownedPtr<IPWL_Filler_Notify> m_pFillerNotify;
 
  private: