src/macosx/classes/sun/lwawt/macosx/LWCToolkit.java

@@ -906,6 +906,11 @@
     }
 
     private static boolean isValidPath(String path) {
         return !path.isEmpty() && !path.endsWith("/") && !path.endsWith(".");
     }
+
+    @Override
+    protected PlatformWindow getPlatformWindowUnderMouse() {
+        return CPlatformWindow.nativeGetTopmostPlatformWindowUnderMouse();
+    }
 }