Why uBlock Origin Is More Than Just an Ad Blocker

uBlock Origin is widely regarded as the most efficient browser-based content blocker available. It runs in every major browser, uses minimal memory, and supports an incredibly flexible rule engine. Most users install it and forget it — but unlocking its advanced features transforms it into a full privacy and security tool.

Getting Started: Enable Advanced Mode

By default, uBlock Origin runs in "easy mode." To access dynamic filtering and per-site rules, you need to enable Advanced User mode:

  1. Click the uBlock Origin icon → open the Dashboard (gear icon).
  2. Under the Settings tab, check "I am an advanced user".
  3. The popup will now show a two-column dynamic filtering matrix.

Understanding Filter Lists

uBlock Origin ships with a curated set of filter lists. The most important ones to understand:

  • EasyList: The original ad-blocking list, maintained by the community.
  • EasyPrivacy: Focuses on tracking scripts and beacons.
  • uBlock Filters: The project's own maintained filters, often faster to update.
  • Peter Lowe's Ad and Tracking Server list: Excellent for blocking analytics domains.
  • Annoyances lists: Blocks cookie consent banners, newsletter popups, and social widgets.

To add extra lists, go to Dashboard → Filter Lists, scroll to "Custom" at the bottom, and paste in any raw filter list URL.

Writing Custom Filters

Custom filters use the Adblock Plus filter syntax. Here are the most useful patterns:

Block a Specific Domain

||ads.example.com^

The || anchors to the domain start, and ^ is a separator (matches end of domain or slash).

Block a URL Containing a String

/tracking-pixel/

Cosmetic Filtering (Hide Elements)

example.com##.cookie-banner
example.com##div[id^="ad-slot-"]

The ## separator triggers element hiding using CSS selectors. Use your browser's inspector to find the right selector.

Whitelist an Entire Site

@@||trusted-site.com^$document

Dynamic Filtering: Blocking by Resource Type

With Advanced Mode enabled, the popup matrix lets you block or allow resources by type (scripts, frames, images) on a per-site basis. Useful approaches include:

  • Block all 3rd-party scripts globally — enables JavaScript only from the first-party domain. Highly effective at stopping trackers.
  • Block all 3rd-party frames — prevents embedded iframes from social networks and ad exchanges.
  • Use the per-site column to whitelist trusted sites on a case-by-case basis.

The Element Picker: Block Without Writing Code

Don't want to write CSS selectors manually? Use the built-in element picker:

  1. Click the uBlock Origin icon → click the eyedropper icon.
  2. Click any element on the page you want to hide.
  3. uBlock suggests a CSS selector — refine it if needed, then click Create.

This is perfect for hiding persistent cookie banners, sticky headers, or newsletter overlays that aren't covered by default lists.

Useful Tips

  • Use the logger (clock icon in the popup) to see every network request in real time — great for debugging broken sites.
  • Export your settings regularly via Dashboard → Settings → Back up to file.
  • The $important option forces a rule to override whitelist exceptions — useful in edge cases.
  • Combining uBlock Origin with a network-level blocker (Pi-hole or AdGuard Home) gives you both browser-level and OS-level protection.