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I alt-tabbed to Windows 10, but cannot alt-tab back in. Clicking on Sacrifice in the task bar does nothing, either.

I haven't saved in a while, so would prefer not to kill it off.

When back in Windows 10, it stays in the same low res 4:3 ratio instead of returning to native 1920x1200. I don't know if the game is running full screen or some kind of windowed full screen. I just installed it so it is whatever is the default (though I did crank up graphics to max otherwise.)

Any ideas?