Oh, boy... Bewertet mit 2 von 5 Sternen
First, note that other user has taken recently the ownership of this add-on, as the original developer, Captain Caveman, left the support and development for all his add-ons a few months ago. He offered his work to those interested.
And now we see the first related news. As Dillanski mentioned, be aware: the recent updates (since 22.214.171.124... but it's still harmless; 126.96.36.199+ are ugly) only adds a new option, *enabled by default*, for to integrate a "price comparison (WizeShoppy)". First time that I hear about it, but only by the source code added for its integration, I see that it works in a very intrusive way over all your web navigation, and, in general, I recommend stay away of things as this.
188.8.131.52 is still in a "waiting aproval by some AMO reviewer" state, so users (yet) didn't received this update.
Independently of the choices of the new developers for to monetize this add-on, not having a single mention of it in the release notes, is a fishy behaviour (EDIT 20/3: Now it's mentioned). And it seems that with other add-ons she(?) is doing the same.