Firefox 149 (March 2026) silently bundled Brave’s Rust-based adblock-rust engine, disabled by default with no UI; this extension surfaces a management interface for it.
Key Takeaways
adblock-rust shipped in Firefox 149 with no release notes mention, no UI, controlled only by two about:config prefs: privacy.trackingprotection.content.protection.enabled and privacy.trackingprotection.content.protection.test_list_urls.
Standard WebExtension APIs cannot write arbitrary about:config prefs; the extension automates only the ETP toggle via browser.privacy and guides users through the two-pref manual setup.
Filter list manager supports 8 quick-add presets including EasyList, EasyPrivacy, uBO Filters, AdGuard Base, and Peter Lowe’s list; builds the pipe-separated pref value automatically.
Permanent installation requires setting xpinstall.signatures.required=false in Firefox Release; the extension is unsigned and cannot go through normal AMO distribution without Mozilla’s privileged signing pipeline.
An earlier version used experiment_apis to write prefs directly, but that only works on Nightly and Developer Edition, so the current design dropped it for standard MV3 APIs.
Hacker News Comment Review
Practical utility is the central question: commenters with uBlock Origin + ETP already see no ads and want a concrete reason to switch; no commenter supplied a clear performance or coverage benchmark favoring adblock-rust over uBO.
YouTube ad blocking is a reported gap – the Rust engine with standard filter lists leaves YouTube ads intact, which uBO handles reliably; this limits the extension’s appeal to power users who already rely on uBO.
Skepticism about browser-native blocking runs alongside the technical questions, with one commenter framing it as a trust issue: blocking should stay in user-controlled extensions independent of vendors with ad industry relationships.
Notable Comments
@RandomGerm4n: confirmed YouTube and some other ad-heavy sites still show ads with adblock-rust + filter lists, where uBO succeeds.
@kgwxd: “Tracker/Ad blocking should forever be an extension” – opposes browser-vendor-controlled blocking on principle.
