Add back atom:link tag to RSS

layouts/_default/rss.xml

@@ -39,8 +39,10 @@
 {{ end }}
 
 {{ printf "<?xml version=\"1.0\" encoding=\"utf-8\"?>" | safeHTML }}
-<rss version="2.0" {{ with $language }} xml:lang="{{ . }}" {{ end }}>
+<rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom" {{ with $language }} xml:lang="{{ . }}" {{ end }}>
     <channel>
+        {{ printf `<atom:link href="%s" rel="self" type="application/rss+xml"/>` $page.Permalink | safeHTML }}
+
         {{ with $copyright }}
             <copyright>{{ . }}</copyright>
         {{ end }}