README.md in prawn-emoji-4.0.0 vs README.md in prawn-emoji-4.1.0

- old
+ new

@@ -88,10 +88,10 @@
 
 2.5, 2.6, 2.7
 
 ### Prawn
 
-2.2+
+2.2, 2.3
 
 ## Contributing
 
 Bug reports and pull requests are welcome on GitHub at https://github.com/hidakatsuya/prawn-emoji.