Rated 4 out of 5 stars

I recently installed this reader and I like it. The only feature that I would like to see is a configurable refresh (say, 1 to 120 minutes). Maybe the toolbar icon could flash to show the number has changed recently.

This review is for a previous version of the add-on (2.1.1.1-signed). 

You could define the automatic refresh delay from the option tab in the update menu.

To flash the unread number you could use a pinned tab with the "Tab badge" Firefox add-on.