diff -r 2a4ca86cc2b7 Lib/webbrowser.py
--- a/Lib/webbrowser.py	Mon Jul 30 17:45:54 2012 -0400
+++ b/Lib/webbrowser.py	Tue Jul 31 01:38:41 2012 +0300
@@ -267,6 +267,7 @@
 
         args = [arg.replace("%s", url).replace("%action", action)
                 for arg in self.remote_args]
+        args = list(filter(None, args))
         success = self._invoke(args, True, autoraise)
         if not success:
             # remote invocation failed, try straight way