FULL PRODUCT VERSION :
openjdk version "14-ea" 2020-03-17
OpenJDK Runtime Environment (build 14-ea+17-721)
OpenJDK 64-Bit Server VM (build 14-ea+17-721, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Mac OS X

A DESCRIPTION OF THE PROBLEM :
NullPointerException was thrown when maximized Frame and expanded Choice.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. Compile and launch the attached sample
2. Maximize the frame by double clicking title bar (Not full screen)
3. Open Choice component
=> NullPointerException was thrown.

EXPECTED VERSUS ACTUAL BEHAVIOR :
Expected:
No exception
Actual:
Exception was thrown and Choice was not expanded.
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at java.desktop/sun.lwawt.macosx.LWCToolkit.getScreenInsets(LWCToolkit.java:482)
at java.desktop/javax.swing.JPopupMenu.adjustPopupLocationToFitScreen(JPopupMenu.java:348)
at java.desktop/javax.swing.JPopupMenu.showPopup(JPopupMenu.java:828)
at java.desktop/javax.swing.JPopupMenu.setVisible(JPopupMenu.java:785)
at java.desktop/javax.swing.JPopupMenu.show(JPopupMenu.java:959)
at java.desktop/com.apple.laf.AquaComboBoxPopup.show(AquaComboBoxPopup.java:141)
at java.desktop/javax.swing.plaf.basic.BasicComboPopup.togglePopup(BasicComboPopup.java:1218)
at java.desktop/javax.swing.plaf.basic.BasicComboPopup$Handler.mousePressed(BasicComboPopup.java:897)
at java.desktop/java.awt.AWTEventMulticaster.mousePressed(AWTEventMulticaster.java:288)
at java.desktop/java.awt.Component.processMouseEvent(Component.java:6634)
at java.desktop/javax.swing.JComponent.processMouseEvent(JComponent.java:3342)
at java.desktop/java.awt.Component.processEvent(Component.java:6402)
at java.desktop/java.awt.Container.processEvent(Container.java:2263)
at java.desktop/java.awt.Component$1.processEvent(Component.java:968)
at java.desktop/sun.lwawt.LWComponentPeer.sendEventToDelegate(LWComponentPeer.java:1223)
at java.desktop/sun.lwawt.LWComponentPeer.handleEvent(LWComponentPeer.java:1212)
at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:5074)
at java.desktop/java.awt.Component.dispatchEvent(Component.java:4845)
at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:772)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:391)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:95)
at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745)
at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:743)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:391)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:742)
at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.*;

public class ChoiceTest
{
    static public void main(String args[])
    {
        Frame f = new Frame("ChoiceTest");
        Panel p =new Panel(new BorderLayout());
        Choice choice = new Choice();
        choice.addItem("aaa");
        choice.addItem("bbb");
        p.add("North",choice);
        p.add("Center",new Canvas());

        f.add(p);
        f.setSize(600, 400);
        f.setVisible(true);
    }
}
---------- END SOURCE ----------