Betterfox is an MIT-licensed user.js preference file that makes Mozilla Firefox more private, secure, and fast without adding third-party code, and it targets everyday Firefox users who want hardened defaults without site breakage.

What it is

Betterfox is a curated user.js file — the configuration file that controls Firefox settings — shipped as plain text and placed in a Firefox profile directory. It grew out of a set of about:config tweaks into an opinionated preference list guided by the law of diminishing returns and the minimum effective dose: it keeps the settings that matter and discards the rest. Every change lives inside Firefox's own preference system, so no extension, binary, or third-party library enters the browser.

The problem it solves is the gap between Firefox's stock defaults, which weigh privacy against telemetry, sponsored content, and broad site compatibility, and the protection a privacy-conscious user wants. Betterfox replaces hand-editing dozens of about:config keys — or copying whatever list a forum post recommends — with one reviewed file that bundles anti-tracking, telemetry, and performance preferences. A separate branch covers Firefox 153 ESR, so both current and extended-support releases are handled.

Key capabilities

• Ships one user.js curated from three named guides: Securefox.js for protecting user data without site breakage, Peskyfox.js for distraction-free browsing, and optional Smoothfox.js for Edge-like smooth scrolling.
• Applies about:config tweaks across anti-tracking, privacy, security, performance, and speed.
• Maintains a dedicated branch for Firefox 153 ESR.
• Documents Common Overrides and Optional Hardening so settings are adjusted rather than accepted blindly.
• Covers secure DNS through a chosen provider as a second layer against ads, trackers, and security threats.
• Pairs with uBlock Origin and the maintainer's recommended filterlists for extension-level ad and tracker blocking.

Who uses it and how

• Individual Firefox users who want hardened defaults without researching each key: back up the profile, download user.js, review the overrides, drop the file into the profile root directory, restart.
• Privacy-focused users who combine Betterfox with uBlock Origin and DNS-level protection, since browser preferences alone cannot block every ad or tracker.
• Users of Firefox forks: Zen incorporated Betterfox in July 2024 and FireDragon in January 2024, and the README advises applying user.js even on those forks because fork changes can reduce effectiveness.
• ESR users, and anyone who wants only the smooth-scrolling piece through Smoothfox.js.

Getting started

Download the raw user.js from the repository (right click, Save Link As…), create a backup profile, review Common Overrides and Optional Hardening, then move the file into the profile folder opened from about:profiles under Root Directory and restart Firefox.

How it compares

The facts name two peers rather than paid products: Zen and FireDragon, Firefox forks that build Betterfox in. Those forks modify the preferences in ways the README says reduce effectiveness, so Betterfox works as the underlying preference layer that stock Firefox, a fork, or an ESR build can adopt directly. The GitHub repository is the only official source; other sites claiming to be Betterfox are not.

When to use it — and when not to

Betterfox is a file, not an application: there is no installer, no updater, and no database, storage, or mail service to operate, but a user copies the file by hand, reapplies it after profile changes, and merges new versions manually. Anyone unwilling to read Common Overrides and Optional Hardening should not apply the whole file, because unreviewed preferences are where site breakage comes from. Organizations that need centrally managed, policy-enforced browser configuration will not find that here — a single user.js is not a management tool.