Waterfox vs Firefox: The ESR Fork With Telemetry and AI Off

Short Answer

Waterfox is the stronger choice for readers who want an Extended Support Release (ESR) build with telemetry removed and machine learning (ML) code paths disabled out of the box. At Ban the Bots, we review browser configurations and privacy controls to determine how software teams handle automated data collection and artificial intelligence (AI). The cost is release pace: Waterfox tracks Firefox Extended Support Release, so new platform features arrive later than on standard Firefox.

The choice between Waterfox vs Firefox comes down to engineering defaults. Firefox added an AI Controls panel in version 148 that lets users turn off its sidebar assistant, link previews, and translations from one menu. Waterfox goes further by stripping out sponsored tiles, deleting telemetry pipelines, and locking configuration flags so local machine learning code cannot execute without deliberate manual intervention.

If you want to evaluate an alternative privacy fork, our comparison of LibreWolf vs Firefox examines how that project handles aggressive anti-fingerprinting configurations. For readers seeking options that avoid the Chromium rendering engine entirely, our index of browsers without AI documents additional independent options.

Waterfox vs Firefox at a Glance

Waterfox and Firefox share the same Gecko platform foundations, but they diverge across data collection defaults, release schedules, and automated features. The following table highlights their technical differences alongside Brave for comparison.

Features Waterfox Removes and Adds

Waterfox strips background diagnostic pipelines and sponsored content while adding integrated privacy utilities directly into the browser shell. Alex Kontos launched the project on 27 March 2011 as a 64-bit Windows build under the Mozilla Public License (MPL) 2.0. Over the years, the software evolved from a performance-focused build into a specialized fork that removes Mozilla commercial integrations.

In a December 2025 editorial titled No AI* Here, Waterfox outlined its core philosophy: when Mozilla began incorporating user telemetry, Pocket integrations, and sponsored tiles, Waterfox removed them. The project operates on the principle that a web browser should serve user commands rather than steer browsing habits. As a result, new profile installations in Waterfox display a clean start page free of commercial article suggestions and promotional partner tiles.

Alongside these removals, the official Waterfox homepage lists several privacy additions built into the desktop client:

• Integrated content blocking: Waterfox includes an out-of-the-box ad and tracking blocker on desktop systems, removing the immediate need to install third-party filtering add-ons.
• Private DNS routing: Waterfox encrypts Domain Name System (DNS) queries and routes them through an Oblivious Hypertext Transfer Protocol (OHTTP) relay, hiding the user's internet protocol address from the resolving server.
• Privacy Containers: Users can isolate website sessions into separate client containers, preventing trackers from correlating identities across different tabs.
• Custom tab layouts: Waterfox integrates Tree Tabs and native vertical tab configurations, giving users flexible navigation arrangements without custom CSS modifications.

Artificial Intelligence Policies and Code Paths

Waterfox enforces an explicit boundary between traditional machine learning tools and automated large language models (LLMs). On 18 September 2026, founder Alex Kontos published a policy statement titled Where Waterfox stands on AI and LLMs, confirming that Waterfox will not incorporate LLMs into the browser. The statement notes that translation has been part of Waterfox for more than seven years, before LLMs were publicly released, and that Waterfox treats it separately from chatbots.

This policy reflects concrete code adjustments established in earlier technical updates. Release notes for Waterfox 6.6.6, published on 9 December 2025, show that the underlying machine learning engine toggle browser.ml.enable defaults to false. The update also set browser.ml.linkPreview.enabled to false and locked access to experimental Labs features. Local machine learning code paths remain unreachable in Waterfox unless an administrator deliberately overrides multiple locked configuration preferences.

When Waterfox updated to version 6.7.0, detailed in the Waterfox 6.7.0 release notes, it maintained this posture against upstream changes. The release disabled the new chat sidebar and associated interface shortcuts introduced on the underlying Firefox 153 platform. The project published its formal LLM Usage Memorandum v1.0 on 23 January 2026, codifying that Waterfox will not ship large language models by default. Users retain the freedom to connect third-party AI assistants through web extensions, but the core binary contains no generative prompts.

Mozilla handles artificial intelligence through a different user experience strategy. Starting with Firefox 148 on 24 February 2026, Mozilla introduced an AI Controls settings panel. This menu provides a master switch labeled "Block AI enhancements" that deactivates sidebar chatbots, automatic tab grouping, link previews, and Portable Document Format (PDF) image descriptions. Firefox ships these tools enabled by default, requiring privacy-conscious users to locate and toggle the preference panel after installation.

Release Channels and Security Patch Timing

Waterfox bases its releases on the Firefox Extended Support Release branch rather than Mozilla's consumer rapid-release channel. Waterfox 6.5.0 launched on 30 October 2024 using Firefox ESR 128. Waterfox 6.6.0 followed on 19 August 2025, upgrading the core to ESR 140 while adding vertical tabs and tab grouping. On 19 August 2026, Waterfox 6.7.0 "Supernova" transitioned the platform to Gecko ESR 153.

Tracking the Extended Support Release channel creates an operational delay for consumer features. New web platform features reach standard Firefox first and arrive in Waterfox at the next ESR platform jump, such as ESR 140 to ESR 153 in August 2026. If your workflow requires immediate access to the latest Web standards as soon as Mozilla ships them, standard Firefox remains the necessary environment.

Security patching follows a different operational pattern. Waterfox backports security fixes from upstream Mozilla repositories directly into its ESR builds. In release 6.6.16, issued on 7 July 2026 and documented in the Waterfox 6.6.16 release notes, the update bundled all security patches developed for the upcoming Firefox ESR 140.13 release. Waterfox users received those vulnerability fixes before Mozilla pushed its official ESR point release. That update also established Qwant as the default search engine across 26 geographic regions.

The desktop edition reached version 6.7.3 on 12 September 2026, running Gecko ESR 153. Users who want to inspect changes across minor updates can review the continuous documentation at the Waterfox documentation index and the main Waterfox releases portal.

The Ownership History Behind Waterfox

Waterfox has changed hands twice. Alex Kontos first released it on 27 March 2011 for 64-bit Windows. The browser gained early adoption among users seeking 64-bit performance and support for legacy XML User Interface Language (XUL) add-ons. That legacy branch, known as Waterfox Classic, had its final published release in November 2022 and was effectively discontinued as of 2026.

In December 2019, digital advertising company System1 acquired Waterfox. The acquisition raised immediate concerns within the open-source community regarding data privacy and ad-tech integration.

Corporate ownership ended three years later. On 3 July 2023, Kontos published an announcement titled A New Chapter for Waterfox, confirming that Waterfox had regained full independence. The transition separated the project from System1 corporate infrastructure entirely.

Waterfox on Android

Waterfox maintains a dedicated mobile client for Android devices that mirrors the telemetry removals found on desktop builds. The application became available on the Google Play Store in November 2023. Users who prefer avoiding app store accounts can download direct Android Package Kit (APK) release files from the project GitHub repository.

On 18 July 2025, Waterfox launched Android version 1.1.0. This release delivered a complete rebuild based on Firefox Extended Support Release architecture. The rebuild removed background telemetry agents, sponsored shortcut tiles, Mozilla experimentation frameworks, and integrated tracking services from the mobile application. The current mobile edition, version 1.2.8 released on 17 September 2026, runs on the Gecko 156.0 mobile engine.

Waterfox vs Brave

Waterfox and Brave target privacy-conscious users through fundamentally different technical foundations. While Waterfox builds on Mozilla's Gecko engine, Brave operates as a Chromium fork created in 2015 by Brendan Eich and Brian Bondy. Our comparison of Brave vs Firefox details how Chromium forks interact with modern web standards, and those architectural trade-offs apply directly here.

Brave ships an AI assistant by default and an opt-in ad program. As outlined on the official Brave overview and Brave Leo page, the browser integrates an AI assistant named Leo into its sidebar. Brave also operates an optional advertising program detailed on the Brave Rewards portal, which distributes Basic Attention Token (BAT) cryptocurrency to users who view opt-in promotions.

Waterfox rejects both commercial cryptocurrency incentives and native AI sidebars. Brave Shields blocks ads and trackers by default, but Brave runs on Google's Chromium engine. Choosing Waterfox keeps an independent Gecko engine active on the web while avoiding sidebar assistant prompts entirely.

Who Should Stay on Firefox

Standard Firefox remains the practical choice for users who depend on rapid platform updates and official Mozilla services. Consumer Firefox ships new platform features first, giving earlier compatibility with experimental web APIs and new Cascading Style Sheets features. Web developers testing new platform capabilities benefit from running rapid-release Firefox rather than waiting for annual ESR transitions.

Standard Firefox is also the build Mozilla supports directly, which matters if you rely on a Mozilla account or need enterprise policy support.

Finally, users who appreciate productivity tools like automated tab organization, link previews, and built-in chat sidebars will find them polished inside Firefox. With the Firefox 148 AI Controls switch, you retain the ability to disable those features whenever you choose, without needing to migrate your workflow to a separate fork.

Verdict on Waterfox vs Firefox

Choose Waterfox if you want a Gecko browser that completely removes telemetry pipelines, sponsored tiles, and machine learning code paths before your first launch. The inclusion of a desktop content blocker and Oblivious HTTP DNS routing makes Waterfox an efficient, pre-configured privacy client. It frees you from auditing settings menus to confirm your data remains local.

This recommendation is not for users who need the latest rapid-release browser standards or organizations requiring official Mozilla enterprise support agreements. Those teams should stay on standard Firefox or evaluate our analysis of Chrome alternatives for other enterprise choices. If you want a browser that includes customizable workspaces, our review of Zen Browser covers another modern Gecko fork, while our guide to Vivaldi vs Brave explores feature-dense Chromium alternatives.

Our verdict would change if Mozilla made data telemetry strictly opt-in across all installation channels, or if Waterfox experienced prolonged delays when importing critical security updates from upstream Firefox Extended Support Release branches. Download the installer from the official Waterfox portal or test the AI Controls settings panel inside your current Firefox setup to settle your Waterfox vs Firefox choice today.

Frequently Asked Questions

Is Waterfox safe?

Waterfox is safe for regular web browsing because it imports security patches directly from the Mozilla Firefox Extended Support Release branch. In release 6.6.16, Waterfox even backported security fixes ahead of Mozilla's scheduled ESR release date. The browser code is open source under the Mozilla Public License 2.0, allowing public inspection of its build scripts and changes.

Does Waterfox have AI?

Waterfox does not include large language models by default and keeps machine learning features disabled. Starting in version 6.6.6, Waterfox set browser.ml.enable to false, disabled link previews, and locked local artificial intelligence code paths. The browser permits on-device translation tools, which have been part of the codebase for over seven years, but rejects chatbot integrations.

Is Waterfox based on Firefox ESR?

Waterfox tracks the Firefox Extended Support Release (ESR) channel instead of Mozilla's four-week rapid-release cycle. Waterfox 6.5.0 ran on ESR 128, version 6.6.0 updated to ESR 140, and version 6.7.0 upgraded the underlying platform to Gecko ESR 153. This cycle prioritizes interface stability over rapid feature rollouts.

Who owns Waterfox?

Waterfox is owned and led independently by original creator Alex Kontos. Kontos launched the project in 2011 and sold it to advertising company System1 in December 2019. In July 2023, Kontos announced that Waterfox had separated from System1 and returned to operating as an independent project.

Is there Waterfox for Android?

Waterfox maintains an Android version available on Google Play since November 2023 and as direct APK downloads on GitHub. Version 1.1.0 rebuilt the mobile client on the Extended Support Release base to remove telemetry, sponsored tiles, and experiment frameworks. Version 1.2.8 runs on the Gecko 156.0 engine.

Sources

• Wikipedia: Waterfox Overview and History
• Waterfox Official Portal
• Waterfox Blog: A New Chapter for Waterfox (July 3, 2023)
• Waterfox Blog: No AI* Here (December 16, 2025)
• Waterfox Blog: Where Waterfox Stands on AI and LLMs (September 18, 2026)
• Waterfox Documentation: LLM Usage Memorandum v1.0 (January 23, 2026)
• Waterfox Documentation: Release Notes 6.6.6 (December 9, 2025)
• Waterfox Release Announcement: 6.6.0 (August 19, 2025)
• Waterfox Release Announcement: 6.6.16 (July 7, 2026)
• Waterfox Release Announcement: 6.7.0 Supernova (August 19, 2026)
• Waterfox Release Announcement: Android 1.1.0 (July 18, 2025)
• Waterfox Documentation: Complete Release Index
• Waterfox Releases Archive
• Mozilla Firefox 148.0 Release Notes
• Mozilla Blog: AI Controls in Firefox
• Brave Software: Company Overview
• Brave Leo AI Assistant
• Brave Rewards and BAT Overview