Fullscreen Windows Standalone player opens on first display instead of main display. https://oc.unity3d.com/index.php/s/2t42IbZjkdvS27Z- in this image first monitor is display nr. 1 (first is always from the left) and the main monitor is display nr. 2 (in windows display settings it is marked as "Main display").

If you start the game full screen, then it opens on the first display, but uses the resolution of the main display. This looks very weird when you have two monitors that have considerably different resolutions. For example, if one of the two displays is tilted 90 degrees, it messes up with "Display.displays[]" resolution list.

Reproducible on 5.3, 5.4.

Repro steps:
1. open project "5.3.3.zip".
2. build to Win Standalone. In player settings set "Default Is Full Screen" (Default is Native Resolution seems doesn't change anything).
3. launch standalone. On dual monitor setup, standalone will launch on the first monitor which is set in Windows Display Settings.

Expected: fullscreen standalone should launch on the main monitor.

Workaround:
use "-adapter N" command line argument from documentation http://docs.unity3d.com/Manual/CommandLineArguments.html