diff --git a/src/nsterm.m b/src/nsterm.m
index 4e88297bc04..8c5eb06641b 100644
--- a/src/nsterm.m
+++ b/src/nsterm.m
@@ -6966,7 +6966,7 @@ This avoids an extra clear and redraw (flicker) at frame creation.  */
                      ordered: NSWindowAbove];
     }
 
-  if (!NILP (FRAME_Z_GROUP (f)))
+  if (FRAME_Z_GROUP (f) != z_group_none)
       win.level = NSNormalWindowLevel
         + (FRAME_Z_GROUP_BELOW (f) ? -1 : 1);