invisible_core

Pure config for a patched Firefox stealth profile - zero Playwright dependency.

seed → fingerprint profile → Firefox prefs, plus patched-binary download, proxy config, geo/timezone resolution, and invisible_core.juggler: the client that drives the engine over its own protocol, with the human input rhythm, which every wrapper below shares instead of carrying a copy. Importing it does not start a browser, which is the point: the same fingerprint config backs an automation wrapper and, through it, an MCP server, without either depending on the other.

(It backed a desktop profile manager too, until that repository was deleted on 2026-08-18. The package it published, invisible-firefox, is still on PyPI.)

The shared foundation used by:

• invisible_playwright - the Playwright automation wrapper (InvisiblePlaywright).
• invisible_selenium and invisible_puppeteer - the Selenium and pyppeteer APIs on the same engine.

And through it, for anyone who would rather prompt than script:

• invisible-playwright-mcp
  • the wrapper as an MCP server, for a client that brings its own model.
• AIHawk - an interface and a model, from one command.

The engine itself lives in firefox_antidetect_patch, a Firefox patched at the C++ source level so the fingerprint is produced by the browser instead of injected into the page.

uv add invisible-core

from invisible_core import (ensure_binary, generate_profile, prepare_session_geo,
                            translate_profile_to_prefs)

profile = generate_profile(seed=42)        # deterministic Bayesian fingerprint
geo     = prepare_session_geo("auto", None)  # zone and language of the exit (here, this machine's public IP)
prefs   = translate_profile_to_prefs(profile, locale=geo.locale, timezone=geo.timezone)
binary  = ensure_binary()                   # path to the patched Firefox binary

Same seed → same fingerprint, every time. The timezone is required: a session without one would run on the host's own zone.

What the fields actually mean

Which surfaces a browser fingerprint is made of, what each one gives away, and why consistency between them matters more than any single value, is written up at the invisible_playwright wiki. Those pages are about the problem, not about this package, and several of them record something we got wrong first. A few that document the exact fields this package generates:

• Pinning fingerprint fields - how pin= interacts with the Bayesian sampler, and which combinations it refuses because they don't occur on real hardware.
• How to make Linux and macOS report real Windows fonts - the font side of generate_profile, and why the family list is bundled rather than sampled from the host.
• Canvas and WebGL fingerprints, identical across OSes - why the same seed produces a byte-identical hash regardless of what's actually running underneath.
• Playwright timezone does not match the proxy IP - the surfaces this package's geo/timezone resolution has to keep in agreement.