New client shutdown bug on mac

On mac when the new client loses connection to the server and asks to either restart or shut down. When one of these options is picked when I launch league again it tells me that another instance is running and i must shut down that instance and try again, but there is no instance running. When i restart my computer i can launch league again. With the old client you were able to allow the instance to keep running or quit that instance and launch then league you opened. Why did you take this away, you should add it back