uBlock Origin

uBlock Origin (uBO) is a content blocker that runs inside your browser. With its default settings, it blocks ads and trackers, and it also blocks connections to sites that spread malware.

This review is for beginners who want to make their browser safer. After reading it, you can do the following:

• Install the real uBlock Origin from an official store
• Turn uBlock Origin off and on for a single site
• Use the logger to see what was blocked

##What uBlock Origin does

uBlock Origin blocks network requests and page elements while a page loads. It decides what to block from filter lists. According to the official README, these lists are enabled by default:

You can add or remove lists in the Filter lists pane of the dashboard. The official wiki warns that more lists make site breakage more likely. If you remove lists, it recommends keeping uBlock filters.

##Supported browsers (as of October 2026)

Chromium-based browsers are moving from Manifest V2 to Manifest V3. uBlock Origin is a Manifest V2 extension, and there is no Manifest V3 version of it. Support therefore depends on the browser.

For Chrome, the same developer publishes uBlock Origin Lite (uBOL). uBOL is a pared-down version rebuilt on Manifest V3. It is available from the Chrome Web Store, Edge Add-ons, Firefox Add-ons, and the App Store for Safari. Its default rulesets include uBO’s own lists, EasyList, EasyPrivacy, and Peter Lowe’s list. Some uBO features are not possible under Manifest V3. uBO is not replaced by uBOL automatically, so you choose whether to switch.

##A safe first try: install it and watch what it blocks

1. Open the official store for your browser (see the table above) and add uBlock Origin from its page. On Chrome, choose uBlock Origin Lite instead.
2. Open a site you visit often, such as a news site.
3. Click the uBlock Origin icon in the toolbar to open the popup. It shows how many requests were blocked on this page and how many domains the page connected to.
4. Click the list icon (Open the logger) in the popup. The logger opens in a new tab.
5. Reload the page. Red rows are blocked requests, and the logger shows which filter matched.

The logger in steps 4 and 5 is a uBlock Origin feature. Whether uBlock Origin Lite has the same feature is unverified.

##Common tasks

If a site looks broken, first turn uBO off for that site with the power button and check whether the problem goes away.

##Cautions

##Read next

• cd ../wiresharkWiresharkrecord your own computer’s traffic and read it
• cat ~/guides/lab-setup.mdSetting up a safe lab