This should be simple to add. Either a menu option to set window position back to default or perform a check to see if a window is positioned outside the usable space. The issue can be seen if the Parameters window is positioned on a secondary monitor then reopen Fusion when the secondary monitor is not available. My specific scenario is using a laptop during the day with two external monitors then in the evening launching Fusion with only the laptop display. Parameter window is not available with no way to get to it.