Notifications supporting browser links may not work in rollup window

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Open Monotony, subscribe to rss feed
2. Wait for messages to show up in rollup
3. Click on a notification in the rollup

What is the expected output?
Open a webpage linked to the notification in rollup like they do when they are 
displayed while @ desktop.

What do you see instead?
No action.

What version of the product are you using? On what operating system?
Growl 2.1.3
Mac OSX Mavericks


Please provide any additional information below.

Original issue reported on code.google.com by second.d...@gmail.com on 3 Jun 2014 at 8:06