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If you are running the desktop build of JavaFX then your only monocle options is Headless. Desktop JavaFX does not support the javafx.platform system property, but you can select Monocle with:
-Dglass.platform=Monocle -Dmonocle.platform=Headless -Dprism.order=sw

Status

What's working:

• Rendering Mouse input and input accelerated rendering on X11
• Rendering Accelerated rendering on Freescale i.MX6 and BeagleBoard xM
• Mouse input with Linux device nodes
• Software rendering to /dev/fb0
• Cursors on OMAP3
• Most Much of HelloSanity is working on BeagleBoard xM

What's not working:

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• Touch, key input
• Freescale i.MX6 Cursor
• Dispman port
• Android port
• DirectFB port
• Nested event loops
• Drag and drop
• Window input grabbing
• Robot input and capture
• Unification with Prism's platform recognition

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