The cosmetic filtering data embedded in the content scripts has been extracted in corresponding JSON files. When a list is enabled, the corresponding cosmetic filtering data from the JSON files, if any, is persisted into the extension's local storage. The cosmetic filtering-related content scripts will load the data from these JSON files on-demand only and matching cosmetic filters will be extracted, then the result is cached in the session storage, ensuring there is no longer a need to perform lookup for the rest of the browser session. As a result this further reduces the time to First Contentful Paint. Related issue: https://github.com/uBlockOrigin/uBOL-home/issues/557 |
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| .github | ||
| assets | ||
| dist | ||
| docs | ||
| platform | ||
| publish-extension@b245171eac | ||
| src | ||
| tools | ||
| .gitignore | ||
| .gitmodules | ||
| CHANGELOG.md | ||
| CONTRIBUTING.md | ||
| eslint.config.mjs | ||
| LICENSE.txt | ||
| Makefile | ||
| MANIFESTO.md | ||
| package-lock.json | ||
| package.json | ||
| README.md | ||
| REMOVED.md | ||
uBlock Origin (uBO)
| Browser | Install from ... | Status |
|---|---|---|
| Firefox Add-ons | uBO works best on Firefox | |
| Edge Add-ons | ||
| Opera Add-ons | ||
| Chrome Web Store | About Google Chrome's "This extension may soon no longer be supported" End of support on Chrome 139 |
|
| Thunderbird Add-ons | No longer updated and stuck at 1.49.2. Later versions require "GitHub - Releases". | |
| GitHub - Releases | Stable and development versions on Firefox, Chromium MV2, and Thunderbird. Must be placed manually into web browsers; the Chromium and Thunderbird versions usually won't auto-update. |
uBlock Origin (uBO) is a CPU and memory-efficient wide-spectrum content blocker for Chromium and Firefox. It blocks ads, trackers, coin miners, popups, annoying anti-blockers, malware sites, etc., by default using EasyList, EasyPrivacy, Peter Lowe's Blocklist, Online Malicious URL Blocklist, and uBO filter lists. There are many other lists available to block even more. Hosts files are also supported. uBO uses the EasyList filter syntax and extends the syntax to work with custom rules and filters.
You may easily unselect any preselected filter lists if you think uBO blocks too much. For reference, Adblock Plus installs with only EasyList, ABP filters, and Acceptable Ads enabled by default.
It is important to note that using a blocker is NOT theft. Do not fall for this creepy idea. The ultimate logical consequence of blocking = theft is the criminalization of the inalienable right to privacy.
Ads, "unintrusive" or not, are just the visible portion of the privacy-invading means entering your browser when you visit most sites. uBO's primary goal is to help users neutralize these privacy-invading methods in a way that welcomes those users who do not wish to use more technical means.
Documentation
| Basic Mode | Advanced Mode |
|---|---|
| The simple popup user interface for an install-it-and-forget-it type of installation that is configured optimally by default. | The advanced popup user interface includes a point-and-click firewall that is configurable on a per-site basis. |
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Visit the Wiki for documentation.
For support, questions, or help, visit /r/uBlockOrigin.
Installation
Firefox
uBO works best on Firefox and is available for desktop and Android versions.
Thunderbird
In Thunderbird, uBlock Origin does not affect emails, just feeds.
Chromium
Microsoft Edge Add-ons (Published by Nicole Rolls until version 1.62. Ownership transfer at version 1.64.)
uBO should be compatible with any Chromium-based browser.
All Programs
Do NOT use uBO with any other content blocker. uBO performs as well as or better than most popular blockers. Other blockers can prevent uBO's privacy or anti-blocker-defusing features from working correctly.
Enterprise Deployment
Release History
Translations
Help translate uBO via Crowdin.
About
Free. Open-source. For users by users. No donations sought.
If you ever want to contribute something, think about the people working hard to maintain the filter lists you are using, which are available to use by all for free.

