Yes, the reason is—as it says in the description—that if you're not in full-screen mode, you can't see all the civilians. Thanks for your comment!
the problem is that full-screen mode does not show the civilians for me. They're still hidden
Oh, okay, so you're in full-screen mode too. You mean the game covers the whole screen? Otherwise, I'm out of ideas—sorry I can't help you then. 😔
