Firefox 149 launches March 24, 2026, with a free built-in "VPN." Mozilla announced on March 17 that the tool hides the user's IP address by routing browser traffic through a proxy server. People in the US, France, Germany, and the UK get 50 GB of monthly data at no cost.
Free VPNs "often come with hidden tradeoffs," Mozilla warned in its blog post. But the company calls its own tool a VPN when it is a browser-level proxy. The technical difference defines what it can and cannot protect. Websites and ad trackers see the proxy's IP instead of the user's real location. Email clients, messaging apps, torrent software, and every application outside Firefox continue to use the real IP.
The ISP can still observe DNS queries unless DNS-over-HTTPS (DoH) is separately enabled in Firefox settings. A full-device VPN built on WireGuard or OpenVPN creates an encrypted tunnel at the OS level that covers all data. The paid Mozilla VPN ($4.99/month, powered by Mullvad's server network) does exactly that. The browser proxy does not.
Every HTTP request passes through an unnamed third party. Mozilla has not disclosed which company operates the proxy infrastructure. Whether it uses Mullvad's network (like the premium product) or a different provider is unconfirmed.
Mozilla's "no logs" claim has not been independently audited.
We're solely focused on building the best browser, and our features over the next few months and beyond are driven by the feedback from our community. We're improving the fundamentals like speed and performance. We're also launching innovative new open standards in Gecko to ensure the future of the web is open, diverse, and not controlled by a single engine.
— Ajit Varma, head of Firefox, Mozilla
Firefox's 50 GB cap covers standard web browsing comfortably. Text-heavy sites, searches, and webmail fit within the limit. Video streaming will exhaust it fast. Whether traffic gets throttled, cut off, or redirected to a paid upsell remains undisclosed.
Opera added a built-in VPN in 2016. Brave integrated Tor in private windows. Mozilla chose a lighter path, avoiding OS-level permissions and kernel-mode complexity, but delivering less protection as a result.
Firefox 149 ships three other features alongside the proxy. Split View puts two web pages side by side in one window. Tab Notes (available in Firefox Labs) lets people attach notes to individual tabs. Smart Window (formerly "AI Window") is an opt-in AI assistant for definitions, summaries, and product comparisons.
The most technically relevant security addition actually shipped in Firefox 148. The Sanitizer API is the first browser-native implementation of a web standard that strips dangerous HTML elements before they enter the DOM (Document Object Model). It addresses DOM-based cross-site scripting (XSS), a class of vulnerability that has plagued web applications for two decades. Developers currently rely on external libraries like DOMPurify or custom sanitization logic, both error-prone. A browser-native API provides a standardized defense that stays current without manual updates.
Firefox is still the only major browser not built on Google's Chromium engine. It runs on Mozilla's open-source Gecko rendering engine. As Chrome, Edge, Brave, Opera, Vivaldi, and Arc converge on Chromium, Firefox's survival depends on features that Chromium cannot or will not offer.
A browser proxy that hides your IP from websites is a real privacy gain for casual browsing. The risk is that "free VPN" branding will convince people they are fully protected when their email client, messaging app, and every background process still transmits over an open connection.
The proxy toggle will appear in Firefox 149 settings on March 24. Anyone who needs protection for email, SSH sessions, API calls, or traffic generated outside Firefox should not treat this as a full VPN replacement. For full-device coverage, Mozilla's paid VPN ($4.99/month) or a third-party WireGuard-based service remains necessary.
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