When using laptop screen (1366x768) and connect external monitor (1920x1080, set as primary), the system tray "windows" (sound control, devices, networks, etc.) appear on the external monitor aprox. 768px from top of screen, instead of opening exactly above the system tray. They seem to open at a position where they would open on the laptop screen.

This also happen with application launcher

Reproducible: Always

Steps to Reproduce:
1. Start session on laptop (smaller) screen
2. Connect external (larger) screen
3. Click klipper|device notifier|network-manager | ... in system tray

Actual Results:  
The corresponding window is opened in the middle of the screen (using pixel height of the other screen as bottom position)

Expected Results:  
The window should appear right above the system tray.