Screen content moved right, even in tests

[PlayerWithoutName]

Hello, I saw that when my application is started on an ultrawide monitor (21:9, 2560x1080), whole content of window is moved to the right in amount of about 10 pixels, regardless if widow is maximized or not. I know that it is not my fault because it happens even in tests and demos. Only rendering is messed up because menu clicks are interpreted right (they are registered from border to the place where they should end, so they are not displaced).
Here is screenshot:

[MobiDevelop]

This is better suited for the forum.