Can you reuse the same JMenuBar on two different JFrames on OS X as a screen menu bar? (Answer: no.)

ReuseJMenuBarOSX.java

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.WindowConstants;

/**
 * On OS X, with a screen menu bar, you cannot reuse a JMenuBar between two
 * JFrames. Upon adding it to the second, it is removed from the first.
 */
public class ReuseJMenuBarOSX {

	public static void main(final String[] args) {
		System.setProperty("apple.laf.useScreenMenuBar", "true");

		final JMenuBar menuBar = new JMenuBar();
		final JMenu file = new JMenu("File");
		menuBar.add(file);
		final JMenuItem fileNew = new JMenuItem("New");
		file.add(fileNew);

		final JFrame frame1 = new JFrame("First");
		frame1.getContentPane().add(new JButton("First"));
		frame1.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
		frame1.setJMenuBar(menuBar);

		final JFrame frame2 = new JFrame("Second");
		frame2.getContentPane().add(new JButton("Second"));
		frame2.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
		frame2.setJMenuBar(menuBar);

		final int offsetX = 200, offsetY = 50;
		frame1.pack();
		frame1.setLocation(offsetX, offsetY);
		frame1.setVisible(true);
		frame2.pack();
		frame2.setLocation(frame1.getWidth() + offsetX + 10, offsetY);
		frame2.setVisible(true);
	}

}