Jas Adblock blocks ads, trackers, and popups everywhere — including YouTube — the moment you install it. No setup, no account. It also hides self-hosted ad containers via CSS, since network blocking alone can't reach those, and shows a live count of what's blocked, right now and overall, per site. Unlike black-box blockers, the site explains exactly how it works: the real JSON keys it rewrites, the popup blocker's gesture check, every permission justified. Free, open, zero data collected.