xstate: Persisting Parallel State Machines Fails

Description I’m trying to repeatedly externally step a parallel state machine with persistence. I have set up a simple linear machine that goes a -> b -> c -> d and notes entry and exit.

The base machine is

    states: {
      a: {
        entry: ["doEntry"],
        exit: ["doExit"],
        on: { TRIGGER: { target: "b" } }
      },
      b: {
        entry: ["doEntry"],
        exit: ["doExit"],
        on: { TRIGGER: { target: "c" } }
      },
      c: {
        entry: ["doEntry"],
        exit: ["doExit"],
        on: { TRIGGER: { target: "d" } }
      },
      d: { type: "final" }
    }

In the code sandbox I set up 4 tests.
I create a parallel machine which uses two instance of the base machine.

1. Simple Linear works as expected.
2. Simple Parallel also works as expected. You see two entrys to a, two exits of a… etc
3. Step Linear Works, but complains about Warning: No implementation found for action type I would like to know why that is the case, but the output looks correct
4. Step Parallel does not work.

For quick reference, the serialize/deserialize code is snipped below:

function step(machine, jsonState) {
  const service = interpret(machine);

  if (jsonState === null) {
    service.start();
  } else {
    var restoredState = State.create(JSON.parse(jsonState));
    service.start(restoredState);
    service.send("TRIGGER");
  }

  var retVal = JSON.stringify(service.state);
  service.stop();
  return retVal;
}

function parallelStepTest (machine) {
  console.log('start')
  jsonState.b = step(machine, null)
  console.log('step 1')
  jsonState.c = step(machine, jsonState.b)
  console.log('step 2')
  jsonState.d = step(machine, jsonState.c)
}

Expected Result

Step Parallel
start
entry a
entry a
step 1
exit a
exit a
entry b
entry b
step 2
exit b
exit b
entry c
entry c
step 3
exit c
exit c

Actual Result

Step Parallel
start
entry a
entry a
step 1
entry a
entry a
exit a
entry b
exit a
entry b
step 2
step 3

Reproduction

• https://codesandbox.io/s/xstate-parallel-machine-persist-cmh7k

Additional context