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kotlinlang

are there any best practices how to debug coroutines/channels in idea/AS debugger? for example, how to determine the amount of currently running coroutines?

Better debugging experience is on our todo list of improvements. Being able to see a list of running coroutines (and what they are doing) is this one big item in particular. There's nothing much else that you can do, but add logging statements and put breakpoints to help you with debugging.