Firefox is now the last major browser that still supports uBlock Origin

Original Article ↗ Hacker News Discussion ↗

Firefox’s continued support for the full uBlock Origin ad blocker, via the older Manifest V2 extensions API, now sets it apart from Chromium-based browsers like Chrome and Edge that have moved to Manifest V3 and weakened key blocking and anti-tracking capabilities. Commenters debate whether built-in blockers in browsers such as Brave or Vivaldi, or “Lite” versions of uBlock, are adequate substitutes, and how long non-Google forks can realistically preserve legacy APIs. The conversation broadens into worries about Chromium monoculture, the power of advertising-driven browser vendors to shape the web, and whether users are willing to switch browsers to retain strong ad- and tracker-blocking.

Extension model and uBlock Origin

  • Big theme: Manifest V3 removes the powerful webRequest API used by full uBlock Origin; MV3 “Lite” blockers mostly hide elements and rely on static filter lists.
  • Supporters of MV2 stress:
    • MV2 can block requests before they’re made, reducing bandwidth and battery use.
    • It enables anti‑tracking features (e.g., stripping tracking params, CNAME uncloaking, dynamic rules, per‑site scripts).
  • Others argue MV3 plus declarative APIs are a real security improvement against malicious extensions, even if it weakens blockers.

Firefox’s role

  • Firefox is seen as the last major browser with full MV2 and “real” uBO, giving it a rare competitive advantage.
  • Some note Firefox also vets “Recommended” extensions (including uBO) on each update with automated and periodic reviews.
  • Firefox reportedly ships a disabled-by-default built‑in adblocker (adblock-rust, from Brave) that can be enabled via about:config.

Other browsers and workarounds

  • Brave, Vivaldi, and some Chromium forks still support MV2 via patches or flags, but many commenters see this as fragile:
    • Google could fully remove webRequest from Chromium at any time, making these forks harder to maintain.
  • Built‑in adblockers in Brave, Vivaldi, etc. work well for many, but are generally considered less flexible than uBO on Firefox.

Privacy, telemetry, and trust

  • Debate over whether Brave or Mozilla is more trustworthy:
    • Concerns raised about Brave’s funding (e.g., links to big data firms) and past behaviors (e.g., affiliate rewrites).
    • Others point to Mozilla’s data-collection terms and in-product promotions; some moved to forks like LibreWolf/Waterfox.
  • Several note that both projects are open source and telemetry can often be disabled, but distrust remains.

User experience and browser monoculture

  • Many report Firefox + uBO makes the modern web bearable; browsing without an adblocker feels “unusable.”
  • Mixed reports on Firefox compatibility, especially on Linux: some encounter broken sites and unsolvable CAPTCHAs; others say everything works fine and suspect Chrome‑only development.
  • Strong concern about Chromium monoculture and browsers funded by ad businesses; some hope for new independent engines (e.g., Ladybird, Servo) but note ecosystem and funding challenges.