Unmounting a component that contains ReactGantt throws an error about react-gantt HOT 11 CLOSED

/* eslint-disable */
import React, { Component } from "react";
import moment from "moment";
import { render } from "react-dom";
// import ReactGantt, { GanttRow } from "../src";
import ReactGantt, { GanttRow } from "react-gantt";
import util from "util";
import {Switch, Route, Redirect} from 'react-router'
import {BrowserRouter as Router,Link} from 'react-router-dom'
class Parent extends Component {
  render() {
    return (
      <Router>
      <Switch>
        <Route path="/chart" component={Demo}/>
        <Route path="/empty" component={Empty}/>
        <Route path="*" render={() => (<Redirect to="/chart"/>)}/>
      </Switch>
      </Router>
    )
  }
}
class Empty extends Component {
  render() {
    return (
      <div>
        Empty page
        <br/>
        <Link to="/empty">Empty</Link>
        <Link to="/chart">Chart</Link>
      </div>
    )
  }
}
class Demo extends Component {
  componentWillUnmount() {
    console.log("Demo unmounting")
  }
  render() {
    return (
      <div>
        <ReactGantt
          templates={{
            myTasks: {
              title: "My Tasks",
              steps: [
                {
                  name: "Task Phase One",
                  color: "#0099FF"
                },
                {
                  name: "Task Phase Two",
                  color: "#FF9900"
                }
              ]
            }
          }}
          leftBound={moment()
          .set({ hour: 0, date: 30, month: 5, year: 2016 })
          .toDate()}
          rightBound={moment()
          .set({ hour: 0, date: 29, month: 8, year: 2016 })
          .toDate()}
          dateFormat="YYYY-MM-DD"
          debug={false}
        >
          <GanttRow
            title="Task 1"
            templateName="myTasks"
            steps={[
              moment()
              .set({ hour: 0, date: 1, month: 6, year: 2016 })
              .toDate(),
              moment()
              .set({ hour: 0, date: 4, month: 8, year: 2016 })
              .toDate(),
              moment()
              .set({ hour: 0, date: 17, month: 8, year: 2016 })
              .toDate()
            ]}
          />
          <GanttRow
            title="Task 2"
            templateName="myTasks"
            steps={[
              moment()
              .set({ hour: 0, date: 27, month: 2, year: 2016 })
              .toDate(),
              moment()
              .set({ hour: 0, date: 9, month: 7, year: 2016 })
              .toDate(),
              moment()
              .set({ hour: 0, date: 22, month: 7, year: 2016 })
              .toDate()
            ]}
          />
          <GanttRow
            title="Task 3"
            templateName="myTasks"
            steps={[
              moment()
              .set({ hour: 0, date: 12, month: 6, year: 2016 })
              .toDate(),
              moment()
              .set({ hour: 0, date: 2, month: 7, year: 2016 })
              .toDate(),
              moment()
              .set({ hour: 0, date: 2, month: 8, year: 2016 })
              .toDate(),
              moment()
              .set({ hour: 0, date: 24, month: 9, year: 2016 })
              .toDate()
            ]}
          />
        </ReactGantt>
        <Link to="/empty">Empty</Link>
        <Link to="/chart">Chart</Link>
      </div>
    );
  }
}
// eslint-disable-next-line no-undef
render(<Parent/>, document.getElementById("demo"));

    "react": "^16.3.2",
    "react-dom": "^16.3.2",
    "react-router": "4.3.1",
    "react-router-dom": "4.3.1",
    "react-gantt": "2.1.4"

Warning: Failed prop type: Invalid prop `titleStyle` of type `object` supplied to `GanttPopup`, expected `string`.
    in GanttPopup (created by GanttRow)
    in GanttRow (created by Demo)
    in tbody (created by ReactGantt)
    in table (created by ReactGantt)
    in div (created by ReactGantt)
    in ReactGantt (created by Demo)
    in div (created by Demo)
    in Demo (created by Route)
    in Route (created by Parent)
    in Switch (created by Parent)
    in Router (created by BrowserRouter)
    in BrowserRouter (created by Parent)
    in Parent