New system

Inbox.js

import React, { Component } from 'react'
import RenderIfRoute from './RenderIfRoute'
import Message from './Message'

export default class Inbox extends Component {
  render() {
    return (
      <div>
        <h2>Inbox</h2>
        <RenderIfRoute isActive={state => state.routing.activeRoute === 'message'} component={Message} />
        <RenderIfRoute isActive={state => state.routing.activeRoute !== 'message'} component={(props) => <div {...props} />}>
          Welcome to your Inbox!
        </RenderIfRoute>
      </div>
    )
  }
}