dist/index.js
function cleanup () {
    transport$$1.removeListener('open', onTransportOpen);
    transport$$1.removeListener('error', onerror);
    transport$$1.removeListener('close', onTransportClose);
    self.removeListener('close', onclose);
    self.removeListener('upgrading', onupgrade);
  }
function cleanup () {
    transport$$1.removeListener('open', onTransportOpen);
    transport$$1.removeListener('error', onerror);
    transport$$1.removeListener('close', onTransportClose);
    self.removeListener('close', onclose);
    self.removeListener('upgrading', onupgrade);
  }
Remove all listeners on the transport and on self