Multi monitor annoyance/issue

Bit of an issue with 2 monitors: Monitor 1 is on start screen, monitor 2 is on desktop. Open an app on Monitor 1 like Store for example and browse around, hit Windows key to go back to start screen. When I click on monitor 2 to do something in an open application, monitor 1 flips back into the previous app automatically, instead of staying on start screen. I can't imagine this is intended...