Display "Loading..." text while JS is loading

framework/core/less/lib/scaffolding.less

@@ -137,3 +137,10 @@ blockquote ol:last-child {
     margin: 0;
   }
 }
+
+#flarum-loading {
+  text-align: center;
+  padding: 50px 0;
+  font-size: 18px;
+  color: @muted-more-color;
+}

framework/core/views/app.blade.php

@@ -22,11 +22,16 @@
     <div id="alerts"></div>
 
     @if (! $noJs)
+      <script>
+        document.getElementById('flarum-loading').style.display = 'block';
+      </script>
+
       @foreach ($scripts as $file)
         <script src="{{ $forum->attributes->baseUrl . str_replace(public_path(), '', $file) }}"></script>
       @endforeach
 
       <script>
+        document.getElementById('flarum-loading').style.display = 'none';
         @if (! $forum->attributes->debug)
         try {
         @endif

framework/core/views/content.blade.php

@@ -1,3 +1,7 @@
+<div id="flarum-loading" style="display: none">
+  {{ $translator->trans('core.basic.loading_text') }}
+</div>
+
 @if (! $noJs) <noscript> @endif
 <div class="Alert">
   <div class="container">