FIX: multisite CDN support for site customizations

Author: SamSaffron

app/models/site_customization.rb

@@ -144,7 +144,7 @@ def self.stylesheet_link_tag(key, target, content)
   end
 
   def self.link_css_tag(href)
-    # href = (GlobalSetting.cdn_url || "") + href
+    href = (GlobalSetting.cdn_url || "") + "#{href}&__ws=#{Discourse.current_hostname}"
     %Q{<link class="custom-css" rel="stylesheet" href="#{href}" type="text/css" media="all">}.html_safe
   end
 end