function persist(state) {
  return {
    ...pick(state, 'showTransformPanel', 'parserSettings', 'parserPerCategory'),
    workbench: {
      ...pick(state.workbench, 'parser', 'code', 'keyMap'),
      transform: pick(state.workbench.transform, 'code', 'transformer'),
    },
  };
}
Returns the subset of the data that makes sense to persist between visits.