uBlock Origin: The Complete Guide (Settings Most People Never Touch)

People will tell you uBlock Origin is a set-it-and-forget-it extension. Install it, watch the ads vanish, done. I don’t buy that. Leaving it on defaults is like buying a DSLR and shooting in auto for the rest of your life, technically fine, but you’re touching maybe 20 percent of what it does. I’ve run it daily for the better part of a decade. The stuff that actually earns it the title of best free software I know isn’t on the surface, it’s one click deeper: the element picker, dynamic filtering, the per-site switches.

So this is about the parts most people skip. Installing it now that Manifest V3 has reshaped things in 2026 (and yes, that matters a lot if you’re on Chrome), which settings are worth changing, and the power features that fix problems no default setup can. I’ll also argue for whitelisting a few sites on purpose, because blocking everything everywhere quietly costs the open web something.

what manifest v3 changed

Some background first, because it decides which browser you should be on. Chrome extensions run on one of two frameworks, Manifest V2 or V3. The original uBlock Origin leaned on an MV2 API called blocking webRequest, which let it inspect network requests and block them with the full filter logic intact. Google pulled that capability out of Manifest V3. Across 2024 and 2025, Chrome kept switching off MV2 extensions in stages. The catch is that by 2026 the original uBlock Origin just won’t start on regular Chrome anymore.

On Chrome you get uBlock Origin Lite instead, the developer’s MV3 rewrite. It’s a real piece of work and very light. But MV3’s declarativeNetRequest API puts a ceiling on how many filter rules you can have and can’t run some of the more advanced filter types, so blocking comes out thinner, and the dynamic filtering tools I get to later simply aren’t in it.

Firefox kept full support for the APIs uBlock Origin depends on. The developer has said plainly that Firefox is where the extension behaves the way it’s meant to. My honest take for 2026:

Firefox on Android is worth singling out if you’re in India. It runs full uBlock Origin on your phone, and the phone is where most of us actually browse, where every megabyte is going up against your daily Jio or Airtel cap. On a phone where you can’t switch browsers or just won’t, DNS-level blocking is the fallback that catches everything system-wide.

installing it and the day-one checks

Install only from your browser’s official store listing. Search for “uBlock Origin by Raymond Hill” and check the author name. There are copycat extensions with names a hair off from the real one, and a few of them are adware, which would be a grim joke. The real thing is free, has no “Pro” tier, and never once asks you for money inside the interface.

Once it’s in, click the uBlock icon, then the gear, which opens the dashboard. Three things to look at on day one:

1. Under Filter lists, make sure the defaults are on: uBlock filters, EasyList, EasyPrivacy, and the malicious-domain lists. Those handle ads, trackers, and known malware-hosting domains in that order.
2. In the Regions, languages section, turn on the Indian list. IndianList covers Hindi and other Indian-language sites. Indian news and cricket-score sites lean on local ad networks that the global lists tend to miss.
3. Switch on the Annoyances lists if cookie banners and “open in app” nags drive you up the wall. They clear out clutter that isn’t technically advertising.

Don’t enable every list you see. I learned that the hard way once, ticked a dozen extra lists thinking more was safer, and ended up with higher memory use and a couple of broken sites for basically no extra blocking. The big lists already overlap heavily, so the gains aren’t there. These days I run the defaults plus the Indian list plus one annoyances list, and across months of daily browsing an ad that combination missed is rare.

the popup panel, explained properly

Click the toolbar icon on any page. That big blue power button is a per-site switch, not a global one, which trips people up. Click it on a site you want to support and uBlock keeps running everywhere else. This is the whitelisting mechanism, and honestly I’d encourage using it. Think about the sites you read every day, the small independent publishers, the random blog that solved your exact problem at 2 a.m. Their server bills get paid by the ads you never look at. So whitelist the handful you trust, and let the blocker deal with the rest of the web’s trackers and the genuinely nasty ads.

Below the power button the panel shows counts of blocked requests. Turn on advanced mode and it also breaks down every domain the page tried to reach. Watching one Indian news homepage fire off connections to 40-plus third-party domains is, on its own, kind of an education.

the element picker: remove almost anything

The eyedropper icon in the popup fires up the element picker. Hover over any element on the page, a floating widget, a newsletter nag, one of those auto-playing video containers, click it, then drag the slider until exactly the right element lights up, and hit Create. uBlock writes a cosmetic filter that hides that element on that site from then on.

I’m on this constantly with shopping and news sites. The filter lands in My filters in the dashboard, where you can edit or delete it later. A typical entry reads like this:

example-news-site.in###floating-subscribe-banner
example-shop.in##.app-download-nudge

One thing to keep straight. Cosmetic filters hide elements. They don’t block the network request behind them, so the data can still come down the pipe. If you’re trying to save data on a capped plan, network blocking is what counts, meaning the filter lists and the dynamic rules. The mental model I use: cosmetic filters are interior decoration, network filters are the locked front door. You want both. Only one of them keeps the bytes off your data meter.

advanced mode and dynamic filtering

In the dashboard, under Settings, tick I am an advanced user. Now the popup shows a matrix of every domain the page touches, with three columns of clickable cells. That’s dynamic filtering. It behaves like firewall rules sitting on top of the filter lists:

• Noop (grey): let the filter lists decide. This is the default.
• Block (red): block this domain no matter what the lists say, either just on this site or everywhere.
• Allow (green): permit it even when the lists block it. Handy when a payment gateway or a login widget breaks.

My favourite global rule blocks third-party frames, which wipes out a whole class of embedded junk in one go. If you self-host things or run a homelab dashboard like the one in my home lab setup guide, you can green-light your own local domains so nothing ever gets in their way. All of this, though, lives only in the full uBlock Origin on Firefox. Not in Lite.

a few things worth doing

• Update your lists before you complain. A site that suddenly shows ads usually just means your lists are stale. The Filter lists tab has an update button, and otherwise lists refresh on their own schedule.
• Use the logger. The list icon in the popup opens a live log of every request and which filter caught it. When a page breaks, this is the fastest way to figure out why.
• Back up your config. Settings, then Export, saves your lists, custom filters, and whitelist to one file. Restoring it on a new machine takes a few seconds.
• Pair it with network-level blocking. uBlock guards your browser. A Pi-hole guards the TV, the phones, and everything else in the house. Together they cover nearly all of it.

faq

Is uBlock Origin safe? Why is it free?

It’s open source, so plenty of people have looked at the code, and the developer is famous for turning down donations. There’s no business model. That’s exactly why it has no reason to sell “acceptable ads” exemptions the way a few commercial blockers used to.

How much data does it actually save?

It swings a lot from site to site. On ad-heavy Indian news and entertainment sites, blocking usually shaves page weight by something like 20 percent to 50 percent. On a 1.5 GB/day plan, that’s the gap between rationing your evening browsing and just not thinking about it.

A site says “disable your ad blocker.” What now?

Decide whether the site has earned it. If you value it, click the power button in the popup to whitelist it and move on. If not, the Annoyances lists get past a lot of these detection walls, and the logger plus a custom filter handles most of what’s left.

Does it block YouTube ads?

On Firefox with the default lists, mostly yes. The catch is that YouTube and the filter authors are in a never-ending tug of war, so you’ll hit brief stretches where it breaks. On Chrome with uBlock Origin Lite the results are weaker, because MV3 limits which filtering techniques are even available.