A big pest offering no benefit. Rated 1 out of 5 stars
Annoying. Every click outbound from Facebook gets sidetracked and delayed while this thing checks it... then it invariably claims it couldn't, because the "server must be unavailable."
So I unchecked the Facebook option in the add-on. A day later the option had re-checked itself, i.e., refused to honor my choices: EPIC FAIL.
I uninstalled it, would rather rely on the non-annoying add-on LinkExtend and [Avast's plugin] WebRep.