content: import React from 'react';
  import {Platform} from 'react-native';
  import {StateNavigator} from 'navigation';
  import {NavigationStack} from 'navigation-react-native';
  
  export default () => {
    const stateNavigator = new StateNavigator([
      {key: 'home', route: '{tab?}', defaults: {tab: 'home'}},
      {key: 'notifications', route: 'x/y'},
      {key: 'tweet', route: 'tweet/{id}', trackCrumbTrail: true, defaultTypes: {id: 'number'}},
      {key: 'timeline', route: 'timeline/{id}', trackCrumbTrail: true, defaultTypes: {id: 'number'}}
    ], NavigationStack.HistoryManager && new NavigationStack.HistoryManager(url => {
      const {state, data} = stateNavigator.parseLink(url);
      let fluent = stateNavigator.fluent().navigate('home');
      if (state.key === 'home' && data.tab === 'notifications')
        stateNavigator.historyManager.addHistory(fluent.url, true);
      return fluent.navigate(state.key, data).url;
    }));
  
    if (Platform.OS === 'web') stateNavigator.start();
    
    return stateNavigator;
  }
  