On Mac OSX, Component.getMousePosition() returns a null value if the window/frame/dialog on which it is called is disabled. In Windows it returns a value as expected.

Product(s) tested: 8u75b10
OS/architecture: Mac OSX
Error log file (if present):
Reproducible: Always
Reproducible on machine: All Mac machines
Is it a Regression: Not sure - Tested in 8u76, 8u72, and 8u45 and issue was reproducible on all.
Is it a platform specific issue: Yes