Ad-tech setting 'Privacy-Preserving Attribution' is opt-out in Firefox 128

Original Article ↗ Hacker News Discussion ↗

Opt-out vs. opt-in and telemetry

  • Some argue meaningful experiments/features can’t rely on opt-in because hardly anyone enables them; same view applied to debugging telemetry.
  • Others counter that many opt-in features succeed (e.g., extensions, cited opt-in telemetry projects), so “no one would opt in” suggests the feature isn’t user-beneficial.
  • Several commenters say the onus is on developers to make data collection obviously valuable to users (reliability scores, crash feedback), not just to the business.

Implementation and UX concerns

  • The “Privacy-Preserving Attribution” (PPA) setting is enabled by default in Firefox 128.
  • Commenters report the toggle is hard to discover: search for “advertising” in settings finds nothing, while the option exists under “Website Advertising Preferences.”
  • Some worry Mozilla will quietly re-enable such features on updates, citing past behavior with Pocket.
  • At least Firefox for Android Beta is affected (via about:flags); applicability to stable Android builds is unclear.

Privacy, security, and legality

  • Supporters describe PPA as aggregate-only measurement, using multi-party computation (DAP/Prio) jointly run by Mozilla and ISRG; no participant supposedly sees individual user data, and privacy only fails if both collude.
  • Skeptics argue:
    • Any additional data flow to ad tech is an “attack surface” for deanonymization, legal compulsion, or breaches.
    • Aggregate data is still valuable surveillance; users gain no direct benefit.
    • This won’t stop legacy tracking unless those mechanisms are actively blocked.
  • Disagreement on GDPR:
    • One view: no personal data means GDPR doesn’t apply.
    • Another: GDPR covers “any data collection,” so silently enabling this is at least unethical and possibly illegal. Outcome is unclear.

Mozilla’s incentives and reputation

  • Many see this as part of Mozilla’s shift into advertising: heavy dependence on Google search money, acquisition of an ad-tech firm, and collaboration with Meta-linked actors.
  • Some frame Mozilla as “controlled opposition” that ultimately aligns with big ad platforms.
  • The quiet, euphemistic rollout (“privacy-preserving,” minimal announcement) is widely seen as trust-eroding.

Views on advertising and funding the web

  • Multiple “reasons to hate ads” appear:
    • A: tracking and privacy invasion.
    • B: manipulation and attention capture.
    • C: resource theft (CPU, bandwidth), and a major malware vector.
    • D: encouraging unnecessary consumption and environmental impact.
  • Pro-advertising arguments:
    • Ads fund a large part of today’s commercial web; users overwhelmingly pick “free with ads,” and many jobs depend on this model.
    • A privacy-preserving attribution layer might make it politically and economically feasible to kill third-party cookies.
  • Anti-ad respondents reply:
    • Much of the web is unpaid user content; ads mainly enrich intermediaries.
    • The early, largely non-monetized web disproves the claim that the web “needs” ads.
    • Ad blockers are considered the correct response; many refuse any compromise and see ads-as-such as the core problem.

Alternatives and future browsers

  • Several recommend Firefox forks (Librewolf, Waterfox) or Tor Browser, which aim to strip out Mozilla’s ad/telemetry features.
  • Some look forward to new non-Chromium, non-Gecko engines (Ladybird, Servo) but acknowledge they are early, Linux/Unix-focused, and far from feature/performance parity.
  • Others prefer hardened Chrome/Chromium forks, or alternative engines like WebKit-based browsers, as pragmatic near-term options.