Searched for 'Script Block'; Found this; Added it to FF; FF froze completely at >90% usage on 5 parent threads; FF completely unresponsive; Had to force-quit FF and restart; Removed said pain in the derriere. Reported for poor quality.

No way to set it to work purely as a blacklist. It breaks too many websites and I don't want to whitelist every single one of them, I'd rather just blacklist the shady ones.