The new MV3 architecture reflects Google’s avowed desire to make browser extensions more performant, private, and secure. But the internet giant’s attempt to do so has been bitterly contested by makers of privacy-protecting and content-blocking extensions, who have argued that the Chocolate Factory’s new software architecture will lead to less effective privacy and content-filtering extensions.
For users of uBlock Origin, which runs on Manifest V2, “options” means using the less capable uBlock Origin Lite, which supports Manifest V3.
I’ve had librewolf specific bugs absent in firefox, definitely not a strict upgrade.