Fix of unstyled content of the performance bar

app/views/layouts/_head.html.haml

@@ -55,12 +55,13 @@
   - unless use_startup_css?
     = stylesheet_link_tag_defer "themes/theme_#{user_application_theme_name}"
   = stylesheet_link_tag "disable_animations", media: "all" if Rails.env.test? || Gitlab.config.gitlab['disable_animations']
-  = stylesheet_link_tag_defer 'performance_bar' if performance_bar_enabled?
 
   = stylesheet_link_tag_defer "highlight/themes/#{user_color_scheme}"
 
   = render 'layouts/startup_css_activation'
 
+  = stylesheet_link_tag 'performance_bar' if performance_bar_enabled?
+
   = Gon::Base.render_data(nonce: content_security_policy_nonce)
 
   - if content_for?(:library_javascripts)