Compiling this code
FInputModeGameAndUI inputMode;
inputMode.SetHideCursorDuringCapture(false);
SetInputMode(inputMode);
into MyPlayerController.cpp and restarting the editor will start crashing it on startup. I tested it on a new blank C++ project and can successfully recreate the crash every time. The only way to get back into your project is to go to your project folder, open the .sln file and remove or comment out this code then rebuild your project.