similar to JDK-8159963

Ubuntu 16.04 (Unity) + HiDPI + JDK9b122

Please run the following sample:

import javafx.application.Application;
import javafx.scene.*;
import javafx.scene.control.*;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class MenuApp extends Application {

    public Parent createContent() {

        VBox vbox = new VBox(20);
        vbox.setPrefSize(300, 200);
        final MenuBar menuBar = new MenuBar();
        Menu m1 = new Menu("one");
        m1.getItems().addAll(new MenuItem("111"), new MenuItem("222"));
        Menu m2 = new Menu("two");
        m2.getItems().addAll(new MenuItem("aaa"), new MenuItem("bbb"));
        Menu menu = new Menu("menu");
        menu.getItems().addAll(m1, m2);
        menuBar.getMenus().addAll(menu);
        vbox.getChildren().addAll(menuBar);
        return vbox;
    }

    @Override
    public void start(Stage primaryStage) throws Exception {
        primaryStage.setScene(new Scene(createContent()));
        primaryStage.show();
    }

    public static void main(String[] args) { launch(args); }
}

Cannot navigate over the menu items (but the menu become selected when moving the mouse over it)