diff --git a/app/assets/javascripts/comments.js b/app/assets/javascripts/comments.js
index e8127b705..8ec7d28c4 100644
--- a/app/assets/javascripts/comments.js
+++ b/app/assets/javascripts/comments.js
@@ -40,7 +40,7 @@
       $("#js-comment-form-" + id).toggle();
     },
     toggle_arrow: function(id) {
-      $("span#" + id + "_arrow").toggleClass("fa-minus-square").toggleClass("fa-plus-square");
+      $("span#" + id + "_arrow").toggleClass("fa-minus-square fa-plus-square");
     },
     initialize: function() {
       $("body").on("click", ".js-add-comment-link", function() {