Kerbal Space Program

What happens:
Camera position is modified while the game is minimized.

How to reproduce:
Step 1: Play KSP in a mode that would normally respond to mouse wheel input.
Step 2: ALT ESC
Step 3: Do anything involving the mouse wheel outside of KSP, such as reading a web page.

Notes:
Potential minor disorientation in some cases. Though honestly I was reading for quite awhile before I noticed it and what tipped me off was actually the sound of the engine getting further away, not the actual camera.

Solution:
Not processing input while the game window does not have focus. I'm assuming the renderer already has something like this, so maybe using that as a common state object if you don't already have one?