I can reproduce this crash consistently with a dual screen setup, even if I only run the app on the primary screen and never move it to the external monitor.

To reproduce, you will need to plugin an external monitor. The laptop retina display should be the primary screen, and the external monitor should be the secondary screen. You can run the app entirely on the laptop (primary) screen.

1. Run SwingSet2 with the metal pipeline enabled
2. Select the Color Chooser demo
3. Click on the "Gradient 1" button to bring up the color chooser dialog
4. Click around for a while (I used the HSV menu, but it will eventually crash no matter what you do).

I have attached the hs_err log and the Apple crash log