LibreWolf and Mullvad Browser are both hardened Firefox forks aimed at privacy-conscious users who want better defaults than vanilla Firefox provides. They look similar from a distance. They have meaningful differences up close. For users choosing between them, the right answer depends on what specifically you want a privacy browser to do.
This piece is the practical comparison. We have separate long-form reviews of each.
Quick verdict
For most users wanting a hardened Firefox without configuration overhead: Mullvad Browser. Better fingerprinting resistance, official corporate maintenance from a serious privacy organization, smoother out-of-box experience.
For users who want fully open-source maintenance, broader extension flexibility, or a Linux-distribution-friendly browser: LibreWolf. The hardening is comparable; the project is community-maintained and more configurable.
For users who do not specifically care about either advantage: Firefox plus Arkenfox user.js gets you 80 percent of either browser’s benefits with continued access to Firefox-specific features.
Where they overlap
Both browsers share these characteristics:
- Built on Firefox Stable or ESR, depending on release version
- Telemetry disabled by default
- No Pocket integration
- Aggressive default privacy settings
- uBlock Origin pre-installed (LibreWolf bundles it; Mullvad Browser does too)
- Cookie partitioning enabled
- Reasonable defaults for common privacy preferences
- Free, open source, and donation-supported
For a user who would otherwise spend hours configuring Firefox manually, either browser saves significant effort.
Where Mullvad Browser is stronger
Fingerprinting resistance is genuinely better. Mullvad Browser inherits the Tor Browser’s letterboxing (the technique of constraining viewport size to standard increments to prevent screen-size fingerprinting) and font rationalization. LibreWolf has fingerprinting resistance enabled but does not implement letterboxing.
The user agent is non-unique by design. All Mullvad Browser users send the same user agent string, making the browser fingerprint less useful for tracking. LibreWolf’s user agent is also non-distinctive but in different ways.
The corporate maintenance is more institutional. Mullvad Browser is a collaboration between Mullvad VPN and the Tor Project, both of which are funded organizations with privacy missions. LibreWolf is a community project funded by donations; the ongoing maintenance depends on volunteer time.
The release cycle is more disciplined. Mullvad Browser releases roughly every 4 to 6 weeks tracking Firefox ESR. LibreWolf releases more frequently but updates can sometimes lag Firefox upstream by a few days.
Where LibreWolf is stronger
Configuration is more flexible. LibreWolf exposes more settings and is more amenable to user customization. If you want to enable a specific feature that Mullvad Browser keeps disabled (like a specific WebRTC behavior or a particular font setting), LibreWolf makes this easier.
The Linux distribution support is broader. LibreWolf is packaged in most major Linux distros’ repositories (Arch, Debian, Fedora, openSUSE, Ubuntu, etc.), often with native package management. Mullvad Browser is available as a generic Linux build but is less integrated.
The community is more developer-focused. The LibreWolf community has more discussion of advanced configurations, experimental setups, and edge cases. For users who like tinkering, this is valuable.
The Search engine flexibility is broader. Both default to private search engines, but LibreWolf makes it easier to add and configure custom search providers.
Where neither is strong
Both browsers struggle with sites that depend heavily on specific browser identification or that fingerprint extensively for fraud detection. Some banking sites, some payment processors, some ticketing services may have issues. Both browsers document workarounds.
Neither has dedicated mobile versions. The closest mobile equivalents are Tor Browser for Android (extremely hardened, slow due to Tor routing), DuckDuckGo Browser (hardened but different approach), or Firefox Mobile with manual hardening.
Neither has the brand recognition of Brave or Firefox. Recommending these to non-technical users requires more explanation.
How they compare on specific use cases
For daily web browsing where most sites work: both are fine. Mullvad Browser slightly more polished out of box.
For research where you want to leave minimal trace: Mullvad Browser, because the fingerprinting resistance is more thorough.
For development work where you need browser flexibility: LibreWolf, because the configuration options are richer.
For Linux desktop integration: LibreWolf, because of distro packaging.
For users who will not customize anything: Mullvad Browser, because the defaults are tuned for non-customizers.
Performance
Both are based on Firefox and have comparable performance. In side-by-side use:
- Page load times are essentially identical
- Memory usage is similar (Firefox-typical, around 1 to 2 GB for a busy session)
- Startup time is similar
- JavaScript performance is identical
The hardening overhead is small enough to be unmeasurable in real use.
Update mechanism
Mullvad Browser has its own update channel that pushes updates automatically when available. The user is notified when an update is ready and can apply it.
LibreWolf updates through the package manager on Linux (when installed via package), through the LibreWolf installer on Windows and macOS, or through manual download for portable installs. Distro packages typically lag a few days behind upstream releases.
For security update timeliness, Mullvad Browser is slightly more responsive due to the controlled update channel.
Security audit history
Mullvad Browser inherits the Tor Browser’s security review history, which is extensive (Tor Project has been audited multiple times). The Mullvad Browser additions have been reviewed by Mullvad’s internal security team.
LibreWolf has not had formal independent security audits (it is a community project), but the build process is reproducible and the patches against Firefox are publicly reviewable.
For users who specifically want institutional audit coverage: Mullvad Browser. For users who value reproducibility and public review: both.
Long-term outlook
Mullvad Browser depends on continued funding from Mullvad VPN and the Tor Project. Both organizations have stable funding situations as of 2026.
LibreWolf depends on continued community contribution and donations. The project has been actively maintained for several years.
Neither has obvious risk of being discontinued in the near term. Both have funding models that should be sustainable for the foreseeable future.
A specific recommendation
For someone choosing today, having tried neither:
Try Mullvad Browser first. It is the more polished product and the defaults are well-chosen. You will probably stick with it.
Try LibreWolf if Mullvad Browser specifically does not fit your needs (fingerprinting resistance breaks too many sites you use, you need a specific Linux package management setup, you want more configuration flexibility).
Try both for a week each. The browsers are close enough in functionality that personal preference will distinguish them.
Try neither if vanilla Firefox plus Arkenfox configuration is your existing setup and it works. The marginal benefit of switching is small.
Related: Mullvad Browser long-term review, Hardening Firefox with Arkenfox