diff --git a/src/window.c b/src/window.c
index 12a212a85ac..da80fabe33f 100644
--- a/src/window.c
+++ b/src/window.c
@@ -8213,6 +8213,8 @@ init_window_once (void)
 
   minibuf_selected_window = Qnil;
   staticpro (&minibuf_selected_window);
+  old_selected_window = Qnil;
+  staticpro (&old_selected_window);
 
   pdumper_do_now_and_after_late_load (init_window_once_for_pdumper);
 }