调试：为什么特定路由不起作用？

Question

根路由以及/ about / foo和/ about / bar起作用，但是由于某些原因，/ about / foo / bar不起作用。出现错误消息“无法加载资源：服务器响应状态为404（未找到）”。

import React from 'react';
import AboutMenu from './about-menu.js';
import Home from './home';
import NotFoundPage from './NotFound';
import {hot} from "react-hot-loader";
import {Route, Switch} from "react-router-dom";

class App extends React.Component {
    render () {
        return (
            <div className="app">

            <Switch>

            <Route exact path='/' component={Home}/>
            { ["/about/foo","/about/bar","/about/foo/bar"].map((path,i) => 
             <Route key={i} path={path} component={AboutMenu}/>)
           }

            <Route component={NotFoundPage}/>
           </Switch>
            </div>
        );
    }
}

export default hot(module)(App);