uBO Lite is a browser content blocker extension built on the Manifest V3 API.
The tool addresses ad and tracker blocking while operating under MV3's stricter constraints by using a declarative filtering approach. Rather than running a persistent background process, uBO Lite relies on the browser's native capabilities to inject CSS and JavaScript for content filtering. This means the extension consumes no CPU or memory during normal browsing; the service worker only activates when you interact with the popup panel or options pages. The default ruleset includes uBlock Origin's built-in filters, EasyList, EasyPrivacy, and Peter Lowe's Ad and tracking server list, with the ability to enable additional rulesets through the options page.
Anyone considering adoption should know that uBO Lite is designed for users who need content blocking on browsers enforcing MV3 restrictions, particularly Chrome, Edge, Firefox, and Safari. It suits projects or deployments where resource efficiency matters and where MV3 compliance is mandatory. The tool supports administrator policies through managed storage, allowing organizations to define settings centrally for their users.
The project maintains active issue tracking separated by category: extension bugs are reported in the main repository, while filter and website issues are reported through an in-extension chat feature when viewing affected sites. Support questions are handled through the repository's discussions section. Release notes are documented in the Releases section with older notes archived in the wiki.
