Updated Add a Custom Service (markdown)

Add-a-Custom-Service.md

@@ -19,4 +19,8 @@ var originalTitle = document.title;
 setInterval(checkUnread, 3000);
 ```
 
+Here is an example code that you can start with:
+
+`(function(){var e=document.getElementsByClassName("unread_countValue"),t=0;for(i=0;i<e.length;i++)t+=parseInt(e[i].innerHTML.trim()); return t;})()`
+
 Once you finish writing and testing your code, it will be a great practice to minify it before pasting it into the Dialog Box into Rambox. To minify it, you can use [JSCompress](http://jscompress.com/).