FIX: Use proper HTML for spinner rather than handlebars

app/assets/javascripts/discourse/controllers/topic.js.es6

@@ -1,4 +1,5 @@
 import ObjectController from 'discourse/controllers/object';
+import { spinnerHTML } from 'discourse/helpers/loading-spinner';
 
 export default ObjectController.extend(Discourse.SelectedPostsCount, {
   multiSelect: false,
@@ -510,11 +511,9 @@ export default ObjectController.extend(Discourse.SelectedPostsCount, {
   }.property('isPrivateMessage'),
 
   loadingHTML: function() {
-    return "{{loading-spinner}}";
+    return spinnerHTML;
   }.property(),
 
-
-
   recoverTopic: function() {
     this.get('content').recover();
   },

app/assets/javascripts/discourse/helpers/loading-spinner.es6

@@ -1,4 +1,7 @@
-Handlebars.registerHelper('loading-spinner', function(property, options) {
-    var spinner = "<div class='spinner-wrap'><div class='spinner'><i></i><i></i><i></i><i></i><i></i><i></i><i></i><i></i><i></i><i></i><i></i><i></i></div></div>";
-    return new Handlebars.SafeString(spinner);
+var spinnerHTML = "<div class='spinner-wrap'><div class='spinner'><i></i><i></i><i></i><i></i><i></i><i></i><i></i><i></i><i></i><i></i><i></i><i></i></div></div>";
+
+Handlebars.registerHelper('loading-spinner', function() {
+    return new Handlebars.SafeString(spinnerHTML);
 });
+
+export { spinnerHTML };

app/assets/javascripts/main_include.js

@@ -45,6 +45,7 @@
 //= require ./discourse/components/visible
 //= require ./discourse/helpers/user-avatar
 //= require ./discourse/helpers/cold-age-class
+//= require ./discourse/helpers/loading-spinner
 
 //= require ./discourse/dialects/dialect
 //= require_tree ./discourse/dialects