diff --git a/lib/html/pipeline/emoji_filter.rb b/lib/html/pipeline/emoji_filter.rb
index <HASH>..<HASH> 100644
--- a/lib/html/pipeline/emoji_filter.rb
+++ b/lib/html/pipeline/emoji_filter.rb
@@ -65,7 +65,7 @@ module HTML
         if context[:asset_path]
           context[:asset_path].gsub(":file_name", "#{::CGI.escape(name)}.png")
         else
-          "emoji/#{::CGI.escape(name)}.png"
+          File.join("emoji", "#{::CGI.escape(name)}.png")
         end
       end
Using File.join to join asset path segments.