A DESCRIPTION OF THE PROBLEM :
If a single instance of a JavaFX program is running the arrow keys can be used to traverse the scene. With two or more instances running the arrow keys do not work.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Start two instances of a JavaFX program and try to traverse the scene with the arrow keys

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
arrow keys traverse the scene of the application with focus
ACTUAL -
arrow keys don't work with two instances running

FREQUENCY : always