Not necessarily.
Probably just a matter of habbit. But when I use the debugger testing my game, I then close the runner when I have come to the point where things start to go amiss and want to work in the developer. When I do that the debug window closes too. I guess I could just click the developer window up on the screen, but then the runner will still be active in the beackground.
When I have corrected whatever error I've found through the debugger I will still have to run the runner again to check if I've corrected the error.