Steps to reproduce:
1. Start any level that has a window, wait for the direction arrows on the windows to disappear
2. Enter clear physics mode
3. Move the mouse over the window; arrow disappears
4. Move the mouse back off the window; arrow reappears
Expected:
Arrow is either always visible, or only appears on mouseover.
Untested:
Does this also apply to preassigned skill / zombie indicators? What happens in levels with multiple windows? Are there similar effects on other object types?
