Octopress filters are now limited to html producing templating languages, Fixes #536

plugins/octopress_filters.rb

@@ -24,12 +24,16 @@ module Jekyll
   class ContentFilters < PostFilter
     include OctopressFilters
     def pre_render(post)
+      if post.ext.match('html|textile|markdown|haml|slim|xml')
         post.content = pre_filter(post.content)
       end
+    end
     def post_render(post)
+      if post.ext.match('html|textile|markdown|haml|slim|xml')
         post.content = post_filter(post.content)
       end
     end
+  end
 end