Merge changes from upstream with the CSS reload fix

app/javascript/mastodon/main.js

@@ -1,12 +1,14 @@
+import * as OfflinePluginRuntime from 'offline-plugin/runtime';
+import * as WebPushSubscription from './web_push_subscription';
+import Mastodon from 'mastodon/containers/mastodon';
+import React from 'react';
+import ReactDOM from 'react-dom';
 import ready from './ready';
 
 const perf = require('./performance');
 
 function main() {
   perf.start('main()');
-  const Mastodon = require('mastodon/containers/mastodon').default;
-  const React = require('react');
-  const ReactDOM = require('react-dom');
 
   if (window.history && history.replaceState) {
     const { pathname, search, hash } = window.location;
@@ -23,9 +25,6 @@ function main() {
     ReactDOM.render(<Mastodon {...props} />, mountNode);
     if (process.env.NODE_ENV === 'production') {
       // avoid offline in dev mode because it's harder to debug
-      const OfflinePluginRuntime = require('offline-plugin/runtime');
-      const WebPushSubscription = require('./web_push_subscription');
-
       OfflinePluginRuntime.install();
       WebPushSubscription.register();
     }