Video summary

Which Browser Leaks Your Data? Mullvad vs LibreWolf vs Firefox

Main summary

Key takeaways

Technology

Tech/privacy comparison summary (Mullvad vs LibreWolf vs Firefox)

The video compares three browsers “out of the box” (no manual hardening): Mullvad Browser, LibreWolf, and Firefox (used as a baseline/control). It evaluates whether they prevent tracking by checking:

1) Tracker blocking / content filtering

Mullvad Browser

  • Detected letter boxing-style behavior to keep window sizes consistent, helping reduce fingerprinting via screen dimensions.
  • Canvas protection that blocks/modifies canvas fingerprinting.
  • Approximately 10 active blocking subscriptions (privacy-focused lists), including categories like:
    • EasyList-style ad blocking
    • cookie notice blocking
    • EasyPrivacy-style tracker/privacy-script blocking
    • additional filters (including uBlock-related lists)

LibreWolf

  • Has canvas protection similar to Mullvad (blocks canvas fingerprinting).
  • Does not implement letter boxing, so window resizing could be used for fingerprinting.
  • Also has approximately 10 active ad/tracker blocking subscriptions, including:
    • protection against URL shortener tracking
    • stripping/removal of URL tracking parameters (ad guard URL tracking protection)

Bottom line: LibreWolf shows strong tracker blocking, but may be weaker against fingerprinting due to missing letter boxing.

2) Fingerprinting resistance (behavioral fingerprint uniqueness)

The tester uses the Cover Your Tracks tool (referenced as “from e.org”) to judge whether the browser fingerprint is unique (trackable) versus randomized/near-random.

  • Firefox: Completely unique fingerprint → easier to track.
  • LibreWolf: Unique fingerprint as well → still trackable.
  • Mullvad Browser: Nearly unique fingerprint → slightly harder to identify than the others.

3) DNS and WebRTC leak protection (even with a VPN)

With a VPN running, the tester checks whether the browser exposes IP-related identity via:

  • DNS leaks (requests bypass VPN)
  • WebRTC leaks (real IP exposed via real-time features)

Results:

  • Mullvad Browser: no WebRTC leaks, and no exposed public/local IP details.
  • LibreWolf: no WebRTC leaks, but shows the VPN-assigned public IP (considered acceptable; indicates WebRTC isn’t as fully disabled as Mullvad).
  • Firefox: similar to LibreWolf: no WebRTC leaks, but shows the VPN-assigned public IP.

4) Default search engine privacy

The tester searches for the same query (“fotech/tech” referenced) to see the browser’s default routing.

  • Mullvad Browser: defaults to DuckDuckGo
  • LibreWolf: defaults to DuckDuckGo
  • Firefox: defaults to Google

Privacy implication (per the video): Google may collect/log more user data for profiling, while DuckDuckGo is positioned as more privacy-aligned.

Overall conclusion from the video

  • Mullvad Browser “takes the crown” as the most privacy-focused out-of-the-box option due to:

    • stronger tracker blocking
    • additional letter boxing (reduces fingerprinting)
    • better fingerprint resistance (nearly unique)
    • best WebRTC protection (omits IP details)
    • privacy-friendlier default search (DuckDuckGo)

  • LibreWolf is close but rated slightly lower because it lacks letter boxing, potentially making fingerprinting easier.

  • Firefox is criticized as weakest in this comparison because it has:
    • very weak default tracker blocking/content filtering
    • a unique fingerprint
    • default search set to Google, framed as less privacy-protective.

Main sources/speakers (as referenced)

  • Host / speaker: The video narrator (“Mard,” “libra wolf,” “I have my VPN running…”), a single channel host speaking throughout.
  • Tool source: Cover Your Tracks (referenced as “from e.org” in subtitles).

Original video