Rated 3 out of 5 stars

Love it! Adds color & shape where there wasn't before! Makes my favorite sites that don't have a favicon that much easier to identify in my favorites bar! love it!

... except when it randomly generated a swastika symbol as a favicon. I know it's random, but is there ANY way to block that shape or swap it for something else if that happens?
pic link:
http://tinyurl.com/26s2wam

This review is for a previous version of the add-on (0.3.2). 

No easy detection

Detecting swastikas in general is not easy. I added some code to block the generation of certain shapes that look like swastikas, but other combinations might also result a similar shape. Besides, except for the most trivial cases, what in your opinion "looks like a swastika" might not look like one at all for others. In my opinion, for example, it is pretty far fetched to say that your link resembles a nazi swastika. (Not any more than it resembles a green cross.) Anyway, if you don't like the icon for a particular site for any reason, you can always add that site to your exception list in the add-on preferences.