Menus inaccessible on Linux with i3 wm

ADDITIONAL SYSTEM INFORMATION :
Ubuntu 20.04, i3wm

A DESCRIPTION OF THE PROBLEM :
When using i3 on Linux, it's not possible to interact with menus in the menu bar. They vanish immediately after being activated, and they appear in the wrong location relative to the menu bar

This used to work in JavaFX 8u261, but it doesn't in JavaFX 14.0.2

REGRESSION : Last worked in version 8u261

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Run the attached program when using the i3 window manager, and try to interact with the menus

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The menus should be useable

---------- BEGIN SOURCE ----------
public class BasicJavaFx
{
    public static void main(String[] args)
    {
        Application.launch(MainWindow.class);
    }
    
    public static class MainWindow extends Application
    {
        @Override
        public void start(Stage primaryStage)
        {
            final Menu file = new Menu("File");
            file.getItems().addAll(
                    new MenuItem("Open"),
                    new MenuItem("Save"),
                    new SeparatorMenuItem(),
                    new MenuItem("Exit")
            );

            final Menu edit = new Menu("Edit");
            edit.getItems().addAll(
                    new MenuItem("Copy"),
                    new MenuItem("Paste")
            );

            final MenuBar menuBar = new MenuBar(file, edit);

            final VBox root = new VBox(menuBar);

            final Scene scene = new Scene(root, 600, 400);
            primaryStage.setScene(scene);
            primaryStage.show();
        }
    }
}
---------- END SOURCE ----------

FREQUENCY : always