code: function _onError (err) {
    if (err.status === 404 || err.statusCode === 404 || err.expose) return
  
    let msg = err.stack || err.toString()
  
    console.error(`\n${msg.replace(/^/gm, '   ')}\n`)
  }
docs: The default `error` handler
  
  @param {Error} err The error object
  @private