I have this happen all the time because I have 2 monitors at the office, but when I'm at home using my laptop to VPN into my office computer, sometimes there are dialog boxes over on the other monitor that I can't see on the laptop. Here is a handy little program I found to help with this problem. It will force all open programs or dialog boxes to pop onto the single viewable monitor. I used to use that Alt -> spacebar -> M technique but this is WAY faster and foolproof which is perfect for me
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