apart from all the adblocking and privacy stuff, gesturify is one of my favourites. i got used to mouse gestures back when opera was still good and happily kept using them in vivaldi. if it wasn’t for this addon, i probably wouldn’t have been able to switch, when google enforced their manifest v3 bullshit.

streaming enhanced is another great one. it automatically skips intro and outro of shows, so you don’t have to fumble around with whatever remote you use. It also shows imdb ratings, so it’s easier to avoid stinkers, that the services are trying to push.

finally, i’d like to mention comet. i know we hate Reddit here, but usually reddit comments are still better than youtube comments.