Steps to reproduce:
1) Build "systray" example.
2) Run it as minimized.(This is normal when application run as minimized at start up for example)
3) Move to hibernate.
4) Plug in monitor with more high resolution then before
5) Resume Windows
You will see the same that in attached screenshot. In this case context menu is shown in the place where system tray was.
The same problem will reproduce when application is moved to the full screen mode. Size of the window will be the same as resolution in previous monitor.
If we use laptops with external monitors it is reproduced often.