Is it possible to observe the ExecutionContext queue/pending Future/task list?

If I setup an EC on top of a fixed-size threadpool like

val threadpool = Executors.newFixedThreadPool(10)
val ec: ExecutionContext = ExecutionContext.fromExecutor(threadpool)

and then schedule more than 10 (maybe way more) Futures on it,

val futs = (1 to 50).map { num => Future {
  Thread.sleep(60000 * 60)
}(ec) }
  case Success(result) =>"got: ${result}")
} )(ec))

is it possible to tell how many and which Futures are waiting to be executed at any given moment?

This is similar to scala - what is the best way to get the number of futures running in background in an execution context? - Stack Overflow, but it jstack -l doesn’t have any EC/Future information.

For querying an underlying pool, see