Rated 2 out of 5 stars

I love the concept. Unfortunately, it does not seem to work with StumbleUpon (or StumbleUpon does not work with it) despite stumbleupon.com being whitelisted for both source and destination. Yes, I could turn it off temporarily while "stumbling," but that is when I most desire protection as I never know where the Stumble button will take me. Anyhow, what happens when you press the "Stumble" button is that StumbleUpon picks a topic, displays the topic and "discoverer" of the page in the StumbleUpon bar, but the page itself is never displayed.

This review is for a previous version of the add-on (0.5.13). 

This works for me when I whitelist stumbleupon.com as an origin (that is, selecting "allow requests from stumbleupon.com" from the menu). If you're still having problems with this, please let me know.