Fix Firefox problems when it wants to render issuable component

app/assets/javascripts/dispatcher.js.coffee

@@ -112,6 +112,13 @@ class Dispatcher
             new NamespaceSelect()
       when 'dashboard'
         shortcut_handler = new ShortcutsDashboardNavigation()
+        switch path[1]
+          when 'issues', 'merge_requests'
+            new UsersSelect()
+      when 'groups'
+        switch path[1]
+          when 'issues', 'merge_requests'
+            new UsersSelect()
       when 'profiles'
         new Profile()
       when 'projects'

app/views/shared/_issuable_filter.html.haml

@@ -51,8 +51,6 @@
           = button_tag "Update issues", class: "btn update_selected_issues btn-save"
 
 :coffeescript
-  new UsersSelect()
-
   $('form.filter-form').on 'submit', (event) ->
     event.preventDefault()
     Turbolinks.visit @.action + '&' + $(@).serialize()