Practical privacy, from the start.
Original uBlock Origin, Strict ETP, and Firefox fingerprinting protection. Active protection without asking everyone to tune dozens of settings. We do not promise anonymity or an unidentifiable fingerprint.
An independent browser · In development
Your space.
Your rules.
A calmer way to browse. Privacy from the start, room to breathe, and local AI that you choose to enable.
Built on Zen and Firefox. Open by nature.
01 Built-in privacy02 Your search, your choice03 Optional local AI04 Open source
What drives the project
Fewer imposed choices.
More control.
Umbral combines the foundations of Zen and Firefox with its own experience. The aim is to browse with less clutter, reduce tracking, and choose which tools belong in your browser.
An interface that gives you room.
Vertical tabs, containers to separate contexts, and a homepage with shortcuts you add yourself. The idea is to keep what matters close and reduce distracting elements.
Services you choose.
Choose your search engine, connect your own SearXNG instance, and decide whether to use built-in password saving or an external manager. Mozilla account sign-in controls have been removed from the interface.
Open about its limits, too.
The source and credits are available. Umbral is a project in development: ETP records are not presented as uBO blocks, and we do not claim performance gains that have not been demonstrated.
Less clutter. More browser.
Practical tools.
Your decisions.
Features already included in development builds, refined through real-world testing.
Protection you can see.
uBlock Origin keeps its original extension, popup and settings. The homepage shows its status and ETP tracker and tracking-cookie records for the last seven UTC days.
Independent search.
DuckDuckGo is the starting point. Choose another engine or add SearXNG using your own URL. Connecting to that instance requires confirmation and does not enable remote suggestions.
Your workspace.
Editable, reorderable shortcuts, inherited containers for new tabs, and extensions beside the address bar. An experience designed to adapt to you.
An assistant, when you want it
AI stays
on your side.
Enable the optional sidebar and connect a local server compatible with the OpenAI API. Umbral does not bundle or run a model itself: you choose the server and model.
Optional · Off by defaultOpening the panel or saving settings does not make requests. Only conversation text is sent when you send a message; pages and browsing history are not collected automatically. Conversations stay in memory, separated by window and between normal and private browsing.
The project, today
Get to know it.
Take your time testing.
Linux with Flatpak is the primary platform and the recommended option. Windows is offered as an experimental ZIP with manual updates.
Linux · Flatpak
Flatpak for Linux x86_64, built and tested during development. This is the primary platform.
Build guide ↗Windows
Experimental ZIP for Windows x86_64. Installation and updates are manual; bugs are expected.
This is not a published stable release. Browser updates are manual; extensions have their own update mechanism.
No hidden fine print
Before you cross
the threshold.
Does Umbral make me anonymous?
No. Blocking and privacy protections reduce exposure, but do not guarantee anonymity or an unrecognizable fingerprint.
Does the AI read my tabs?
Not automatically. It receives the text you send to your configured server. You can open the panel without configuring a server; chatting requires a running, connected compatible model.
What do the privacy cards count?
Records classified by Firefox ETP for today and the previous six UTC days. These are not ads, HTTP requests or uBlock Origin statistics. Zero means a successful query with no records; a failure shows “No data”.
Is this a browser built from scratch?
No. It is a Zen fork, based on Firefox, with its own interface, homepage and integrations. The project retains the credits and licenses of Zen, Mozilla, uBlock Origin and its other components.
Which platforms are available?
Linux with Flatpak is the primary platform. Windows is offered as an experimental ZIP with manual updates.
Documentation
Everything you need to get started.
Guides, privacy and help, all in one place.
Installation and downloads
Test packages and instructions that keep your profiles separate.
Read guide →Documentation
Your guide to starting, configuring and understanding Umbral.
Read guide →Privacy and data
What Umbral protects, what it stores, and when data can leave your computer.
Read guide →Help and reports
Find known limitations and prepare a useful report.
Read guide →The project
Why Umbral exists and what wider distribution still requires.
Read guide →Contribute to Umbral
How to propose reproducible changes without losing persistent sources.
Read guide →A project that starts with you