Basilisk is an independently developed browser built on the Unified XUL Platform (UXP). UXP began as a fork of the Firefox 52 engine and has since evolved into a separate development platform for XUL-based applications, including browsers. Basilisk follows its own development direction rather than tracking current Firefox releases.

Basilisk is not affiliated with Mozilla or the Firefox project. The Basilisk Development Team maintains the browser independently of Mozilla, Moonchild Productions, and the Pale Moon development team.

Basilisk is a full-featured desktop web browser and requires a reasonably modern system to run reliably and with good performance.

Windows requirements

• Windows 7 or later.
• 1 GB of RAM (2 GB or more recommended for heavier use).
• Dedicated GPU strongly recommended.

macOS requirements

• OS X 10.6 or later for Intel 32-bit builds; OS X 10.7 or later for Intel 64-bit builds.
• OS X 10.5 Leopard on PowerPC systems.
• All macOS releases are supported on Apple Silicon systems.
• 1 GB of RAM (2 GB or more recommended for heavier use).
• A GPU supported by the host version of macOS. Hardware-accelerated graphics are recommended for best performance.

Linux requirements

• A reasonably modern Linux distribution with a contemporary userland.
  Release builds for x86_64, i686, and aarch64 are compiled on Oracle Linux 8 (RHEL 8 compatible).
  LoongArch64 builds are built on Loongnix Server 23.
  Distributions with comparable library versions are recommended.
• 1 GB of RAM (2 GB or more recommended for heavier use).
• Dedicated GPU and hardware-accelerated video under X strongly recommended.
• GTK 2.24 or GTK 3.22+ (GTK 4 is not supported).
• GLib and Pango versions compatible with GTK 3.22.
• X.Org with hardware acceleration support.
• libstdc++ provided by a modern system toolchain.

This is typically caused by older desktop environments or MIME detection rules misidentifying the Basilisk binary as a shared library.

You can work around this by launching Basilisk from a terminal, creating a wrapper shell script, or installing a proper .desktop file.

Additional discussion can be found in this forum thread.

You may compile Basilisk with official branding for personal use. Do not expect support for self-compiled builds from the Basilisk Development Team.

Linux or BSD distribution package maintainers who wish to distribute Basilisk with official branding may do so, provided the build closely follows the official mozconfig files and includes the --disable-updater option to ensure updates are managed by the distribution’s package manager.

Official release binaries are provided for:

• Windows (32-bit and 64-bit)
• Linux (x86_64, i686, aarch64, ARMv7, LoongArch64, MIPS64EL, and big-endian PowerPC64)
• macOS (PowerPC, Intel, and Apple Silicon)
• FreeBSD (x86_64)

Linux builds offer GTK2 and GTK3 variants, except ARMv7 and PowerPC64, which are GTK3 only.

All Apple Silicon macOS releases are supported. Intel 32-bit builds support OS X 10.6 and newer; Intel 64-bit builds support OS X 10.7 and newer. OS X 10.5 is supported on PowerPC.

Community members may also provide builds for additional platforms. We encourage the usage of alternative operating systems, processor architectures, and endianness.

No. Basilisk does not support WebExtensions.

Basilisk instead supports XUL and overlay-based extensions, which allow deeper integration and customization than the WebExtensions model.

Available extensions can be found on the Basilisk Add-ons site.

Yes. Basilisk supports language packs, but currently only English is officially maintained. Community contributions for additional languages are welcome.

No. These operating systems are no longer supported and should not be used for general web browsing.

For users who require support on older Windows versions, a third-party fork called Serpent, maintained by roytam1, may be suitable: MSFN thread.

Please note that Serpent is not Basilisk, and issues specific to Serpent should not be reported to the Basilisk development team.

User support is provided through the Basilisk section of the Pale Moon forums.

No. Basilisk uses a single-process architecture by design.

This decision prioritizes stability, extensibility, and compatibility with existing technologies supported by the Unified XUL Platform.

Donations are currently accepted via Monero (XMR). The donation address is listed in the footer of the website.

The GTK version in use is shown under Help → About Basilisk.

Basilisk is developed and maintained by the Basilisk Development Team, an independent group of contributors.

Basilisk is typically released monthly, with additional releases issued as needed for security updates or critical fixes.

There is no fixed release day, as releases are driven by readiness rather than a strict calendar.

The Basilisk project exists to build and maintain a web browser. That is the only purpose of this project. Politics are not part of it.

Do not post political messaging, activism, or ideological arguments in any Basilisk project space. Not in issues. Not in pull requests. Not in discussions. Not on the forums. Nowhere.

Project spaces are for code, bugs, development, and user support. Nothing else. If you bring politics into this project you will be told to stop. If you do not stop you will be removed. If you come back and do it again you will be banned. There will be no debate about this and no exceptions.

The Basilisk project targets X11 on *nix. We do not support Wayland and we are not working toward Wayland support.

Do not open issues asking for Wayland support. Do not submit pull requests attempting to add Wayland support. This is not a goal of the project and it is not going to happen.

If you want to run Basilisk on a Wayland system you can use XWayland. Basilisk works fine in that environment and XWayland is the supported way to run Basilisk in a Wayland environment.

We suggest the usage of XLibre if you want a proper native X11 environment that does not push political views through its development process.

No. Just no.