I have two monitors, whenever I launch a game in fullscreen, some of my other windows (chrome, skype, whatever) switch randomly to my second monitor and stay there when I quit the game, it doesn't always happen but it's always when they weren't minimized. It still happens when I turn off the second screen before launching the game. I do not know if its specific to Windows 10.
Any way to prevent it ? Even a third party app will do.