[Quantum] JavaFX does not paint correctly when a window opens while the screen is locked

JavaFX does not paint correctly when a window opens while the screen is locked. The problem is reproducible on JavaFX 2.2.x and 8.0.

Steps to reproduce:
1) Launch the application (attached).
2) Click the spawn window button.
3) Lock the screen (on windows, WindowsKey + L).
4) Wait about 8 seconds.
5) Unlock the screen.
6) Observe that the spawned window has opened, but nothing is painted!
7) Mouse over the spawned window content.
8) Observe that the window paints correctly.