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I'm runnning Xcode 9.4.1 and when I launch a device simulator they only show a black screen. I know the app does run because I can see the output in the Debug Area at the bottom and it is as expected.The one simulator that does work is for iPhone SE. It launches with the white Apple Logo and the default screen and icons. All the others I have so far tried launch to a black screen, I never see the white Apple Logo or the default iOS screen and icons, just blackness.I have tried :1) cleaning the app and cleaning the build folder2) running in the terminal : sudo defaults write com.apple.CoreSimulator.IndigoFramebufferServices FramebufferRendererHint 3 Then rerunning Xcode3) Deleting the simulator device and re-adding it4) removing the "xcuserdata" directory under my project folderThis is really a HUGE issue that has stalled my app from final release.Any and ALL solutions are most certainly welcome. Apple ?I have a late 2012 mac mini with HD4000 graphics card.Thanks,