Similiar to RT-40689 but on a higher level; if a menubar contains a hidden menu (keyboard traversal does not work). If you start the following application and press F10 and Down, the menu will not open.

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Menu;
import javafx.scene.control.MenuBar;
import javafx.scene.control.MenuItem;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class MenuNavigationWithHiddenMenu extends Application {

    public MenuNavigationWithHiddenMenu() {
    }

    @Override
    public void start(Stage stage) throws Exception {
        stage.setTitle("Menu navigation with hidden item");
        Scene scene = new Scene(new VBox(), 400, 350);
 
        MenuBar menuBar = new MenuBar();
        Menu hiddenMenu = new Menu("Hidden");
        hiddenMenu.getItems().addAll(new MenuItem("never to be seen"));
        hiddenMenu.setVisible(false);
        Menu menuFile = new Menu("File");
        menuBar.getMenus().addAll(hiddenMenu, menuFile);
        menuFile.getItems().addAll(new MenuItem("New"), new MenuItem("Open"), new MenuItem("Quit"));
        
        ((VBox) scene.getRoot()).getChildren().addAll(menuBar);
 
        stage.setScene(scene);
        stage.show();
    }
    
    public static void main(String[] args) {
        launch(args);
    }
}