code: func (sp *ServerPeer) unsubscribeRecvMsgs(subscription spMsgSubscription) {
  	sp.mtxSubscribers.Lock()
  	defer sp.mtxSubscribers.Unlock()
  	delete(sp.recvSubscribers, subscription)
  }
docs: // unsubscribeRecvMsgs handles removing OnRead subscriptions from the server
  // peer.