I updated my Xcode to 8.2 and since then if I try to take a screenshot while debugging it is crashing and then quits.
I tried iOS 9.0 and 10.0 simulators and it happ
For a static screenshot, an easier and faster workaround is to type COMMAND+SHIFT+4, then hit the space bar until the simulator window is selected, then click on the simulator window to save the screenshot.