code: function printBuffer () {
    let { header, prev, next, action, msgs } = displayBuffer
    if (console.group) {
      console.groupCollapsed(...header)
      console.log(...prev)
      console.log(...action)
      console.log(...next)
      console.log(...msgs)
      console.groupEnd()
    } else {
      console.log(...header)
      console.log(...prev)
      console.log(...action)
      console.log(...next)
      console.log(...msgs)
    }
  }
docs: /* istanbul ignore next: debug messaging is not tested