Issues when switching MetroWindow between monitors while maximized

[iankerr]

Do this (you need a 2 monitor system):

-create a basic WPF application with a MetroWindow
-run the program, maximize the window on one monitor
-send the window to the other monitor using Shift-Windows key and an arrow key (eg. Shift-Windows-Right Arrow to send from the left monitor to the right)
-try to send it back to the first monitor using the corresponding keyboard shortcut (eg. Shift-Windows-Left Arrow)

For me, this always fails when trying to send from right to left: I press Shift-Windows-left, and the window is still on the right monitor, maximized. However, if I then "Restore Down", the window will jump to the left monitor.

If I start off with the window on the right maximized, then do Ctrl-Windows-left, then Ctrl-Windows-right, and then Restore Down, then window disappears! It's still there in the taskbar, but I can't seem to get it back no matter what I do.

Both monitors are the same size, however the working area of the right monitor is slightly larger due to the taskbar taking up space on the left monitor. I'm not sure if the difference is because of a resize happening at the same time, or something about switching back to the primary monitor.

[iankerr]

Some further information to help you troubleshoot:

The above behaviour was observed on a Windows 7 system with 2 identical 1680x1050 monitors, scaling set at 100%. The attempted fix doesn't work.

I have another system: Windows 8.1, primary screen 1920x1200 (high DPI small touchscreen), second screen 2048x1152 (desktop monitor).

Windows 8 has per-display dpi scaling. On my 8.1 system, if I set it up to use different scaling per monitor (Control Panel -> Appearance and Personalization -> Display, uncheck "Let me choose one scaling level for all my displays"), then I can reproduce this issue using the above fix. One slight difference: when I "Restore Down" after trying to move back to the primary monitor, the window appears on the 1st monitor, but slightly off-screen to the left. This leads me to believe that on my Windows 7 system, it is moving the window totally off-screen somewhere.

However, if I use the same scale for both monitors (check "Let me choose one scaling level for all my displays"), then the issue goes away using the latest commit. It should also be noted that when I uncheck "Let me choose one scaling...", and select a scale on one end or the other (Smaller or Larger), my system uses the same scale for both monitors, and the issue disappears.