I'm new to this playform and trying to find my way around. I see an option to "Debug Code in Playground". I was expecting to get a standard debugging experience with breakpoints and the variables plus values. It is not obvious whether a breakpoint can be set. Am I just missing missing something in the UI?

Also, it seems that the first time I enter the Playground, the code presented does not contain my modifications, but is the start-from-scratch code. I think that running it once refreshes the Playground, but I'm not sure.