Unable to add/remove MenuItems in (Context)Menu after it is shown (Regression!)

We asynchronously populate a ContextMenu using the Service class.

While the service is running we display a dummy MenuItem with a progress indicator.
When the service is finished we populate the Context Menu with the service result.

This worked fine in 2.2.

With 8.0 b84, I am unable to remove the MenuItem with the progress indicator and I am also unable to add new items to the context menu.

See this example:


import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.concurrent.Service;
import javafx.concurrent.Task;
import javafx.concurrent.Worker;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.ContextMenu;
import javafx.scene.control.Label;
import javafx.scene.control.MenuItem;
import javafx.scene.control.ProgressIndicator;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import javafx.stage.WindowEvent;


public class TestApp5 extends Application {

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


    @Override
    public void start(final Stage stage) throws Exception {

        VBox root = new VBox();

        Label label = new Label("ContextMenu");
        label.setContextMenu(new MyContextMenu());

        root.getChildren().add(label);

        Scene scene = new Scene(root);
        stage.setScene(scene);
        stage.show();
    }

    private class MyContextMenu extends ContextMenu {

        private MyService service;

        public MyContextMenu() {

            final MenuItem progressItem = new MenuItem();
            progressItem.setGraphic(new ProgressIndicator());

            service = new MyService();
            service.stateProperty().addListener(new ChangeListener<Worker.State>() {
                @Override
                public void changed(ObservableValue<? extends Worker.State> observableValue, Worker.State state, Worker.State state1) {
                    switch (state1) {
                        case SCHEDULED:
                            System.out.println("adding progress item");
                            getItems().add(progressItem);
                            break;
                        case SUCCEEDED:
                            System.out.println("removing progress item");
                            getItems().remove(progressItem);
                            System.out.println("adding new item");
                            getItems().add(new MenuItem("new")); // based on service result.
                            break;
                    }
                }
            });

            MenuItem menuItem1 = new MenuItem("First Menu Item");
            MenuItem menuItem2 = new MenuItem("Last Menu Item");

            setOnShowing(new EventHandler<WindowEvent>() {
                @Override
                public void handle(WindowEvent windowEvent) {
                    service.restart();
                }
            });

            getItems().addAll(menuItem1, menuItem2);
        }
    }

    private class MyService extends Service<Void> {

        @Override
        protected Task<Void> createTask() {
            return new Task<Void>() {
                @Override
                protected Void call() throws Exception {
                    Thread.sleep(1000);
                    return null;
                }
            };
        }
    }
}