Files
camoufox/pythonlib/tests/test_launch_environment.py
T
Jake WriterandClaude Opus 5.5 180e6553cc Docs that match the code, one AGENTS.md, dead code removed, and the audit's bug fixes (#787)
* chore: remove build tooling nothing uses

- The developer UI (scripts/developer.py, `make edits`). It depended on
  easygui, which no requirements file declares, and every action it offered is
  a Makefile target: patch, unpatch, workspace, revert, diff. Its two helpers in
  scripts/_mixin.py (is_bootstrap_patch, patch) had no other callers.
- legacy/, the Go launcher deprecated in 2024-11. Nothing built or shipped it.
  Its Makefile targets and scripts/run-pw.py go with it, and so does Go from
  every dependency list and workflow.
- jsonvv/ and settings/camoucfg.jvv. Nothing read the .jvv schema: config is
  validated against settings/properties.json, and the two had already drifted.
  The jsonvv package stays on PyPI.
- Scripts with no caller: bootstrap.py, moztree, setup-wasi-linux.sh,
  package-helper.sh, install-local-build.sh, mozfetch.sh (copied into lw/ but
  never packaged), examples/.
- The pre-ESM Juggler copies JugglerFrameParent.jsm and JugglerFrameChild.jsm,
  and hidden-scrollbars.css. Juggler loads the .sys.mjs actors and deliberately
  no stylesheet, but jar.mn still packaged all three.
- patches/librewolf/*.opt, which list_patches() never picks up; the roverfox
  second pass in patch.py, whose directory no longer exists; the unread
  --no-settings-pane option.
- The CAMOUFOX_PASSWD secret passed to `make fetch` and closedsrc_rev in
  upstream.sh, which nothing reads.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* chore(python): remove dead helpers and a stale dependency

None of these had a caller:
- pkgman: is_supported_path, extract_zip, cleanup and set_version, left over
  from the single-directory install. cleanup() would have deleted every
  installed browser version.
- multiversion.get_cached_repo_names, CONSTRAINTS.as_range,
  fingerprints._load_os_voices, utils._clean_locals, and unused imports.

Also:
- The "Apify Fingerprints" row in `camoufox version`, which has read "?"
  since fpgen replaced BrowserForge.
- lxml is no longer a dependency; nothing imports it.
- The geoip extra now names maxminddb, the module geolocation.py actually
  imports, rather than getting it transitively through geoip2.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* docs: show the cursor paths humanize=True actually produces

The README's cursor video showed the Bezier generator Camoufox replaced
with Cursory's recorded trajectories. scripts/cursor-demo.py drives a real
build with humanize=True and records every mousemove event the page
receives. It writes assets/humanize-cursor.svg, an animated replay at the
recorded speed, so what the figure shows is what a site sees.

The script cannot change the binary, so ci/browser_inputs.py lists it as
non-native and editing it does not invalidate the cached browser.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* chore(python): stop naming BrowserForge in user-facing text

fpgen replaced BrowserForge, but two LeakWarnings, the NonFirefoxFingerprint
message and the fingerprint_preset docstring still named it. One warning also
linked to a README anchor that no longer exists.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* docs: one AGENTS.md for every agent, a roadmap, and docs that match the code

- AGENTS.md holds the engineering rules for any coding agent, plus the
  repo map, build, patch and test commands that CLAUDE.md used to carry.
  CLAUDE.md now only imports it, so there is one set of rules.
  ci/tribal-rules.yml is the record of settled decisions it points to.
- ROADMAP.md lists planned work, each item linked to its issue.
- README:
  - fpgen and the coherence check replace BrowserForge;
  - the patch workflow uses the make targets instead of the removed
    developer UI;
  - letter-spacing noise is described as off by default, as it is.
- docs/:
  - beta-testing-ff146.md removed;
  - patch-upgrading-guide rewritten around the make targets;
  - per-context-patches without the canvas patch that no longer exists,
    and with measured preset counts;
  - playwright-maintenance without the JSM wrapper that does not exist;
  - smaller fixes in MEDIA-DEVICES, input-dispatch and FONTS.
- ci/README: every job, and the real shard, skiplist and entry-point lists.
- pythonlib, tester and patch-dependency READMEs corrected against the code.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(pythonlib): handle headless='virtual' in launch_server

launch_server() is documented to take the same arguments as Camoufox(),
but passed headless='virtual' straight to launch_options(), so the server
launched with no Xvfb display. Start a VirtualDisplay the way Camoufox()
does, launch headful on it, and kill it when the server process exits or
the launch fails.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* chore(python): remove fontprobe, which nothing called

fontprobe listed the fonts installed on the host, for a `camoufox fonts`
command that was never added. It has nothing to do with the font bundle
Camoufox serves to pages.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* chore(license): the Python launcher is MIT; the browser stays MPL-2.0

The Python package has always been published to PyPI as MIT (#727), but
pythonlib/ shipped no licence file, and the repo's LICENSE is the browser's
MPL-2.0. MPL is copyleft per file. It covers the modified Firefox sources, not
a separate launcher that drives the browser over Playwright. So
pythonlib/LICENSE now carries the MIT text its metadata already declares, and
a Licensing section in the README says which part is which.

Closes #727.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(python): fingerprint_preset=False no longer turns presets on

launch_options checked `fingerprint_preset is not None`, so passing False
drew a random bundled preset, the opposite of what was asked. It now uses a
truthiness check, and a test proves that None and False never draw a preset.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* ci: bring the release workflow in line with the tests build job

build.yml had drifted from tests.yml. It ran actions at v1/v2 on a
retired Node runtime, prepared the source tree with bare make calls
that fail the whole release on one dropped connection, and built with
a different Python than every pull request is tested with.

- Pin every action by commit SHA, at the major versions tests.yml uses
  (checkout v4, setup-python v5, upload/download-artifact v4, the same
  remove-unwanted-software SHA), and action-gh-release v2. The release
  job holds contents: write, so it should not follow a movable tag.
- Prepare the tree with `python3 -m ci.run_prepare`, as the tests build
  job does. BUILD_TARGET is set from the matrix so `make dir` writes the
  right mozconfig and Rust targets; multibuild.py then finds _READY and
  builds without re-patching. mach's toolchain bootstrap ignores the
  mozconfig, so running it after `dir` bootstraps the same toolchains.
- Build with Python 3.12, the version the tests build job compiles with.
- Default the workflow to no permissions; the build job gets
  contents: read and the release job keeps contents: write.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(python): NewContext looks up a proxy's exit IP through the right URL, or fails

NewContext derives the context's WebRTC IP and timezone from the proxy's exit
IP. That lookup had two defects, and both left the context showing the
host's values while its traffic went through the proxy:

- It built its own proxy URL with urlparse, which reads a scheme-less server
  such as "1.2.3.4:8080" (a form Playwright accepts) as scheme "1.2.3.4" with
  no host. urllib could not use a SOCKS proxy at all.
- Any failure was swallowed, and the context opened without the values.

The URL is now built with Proxy.as_string(), which the geoip launch path
already uses (scheme-less means http). The lookup goes through requests,
which handles SOCKS, and a failed lookup raises InvalidIP, naming the two
options that skip it. The tests cover scheme-less, http and socks5 servers
with credentials, both failure modes, and the case where no lookup is needed,
for NewContext and AsyncNewContext.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix: stop generating a canvas seed, and drop config keys nothing reads

The browser has not noised the canvas since #528, and no patch reads
canvas:seed (#721). The launcher still drew one on every launch and sent it
through CAMOU_CONFIG, and NewContext called a setCanvasSeed that does not
exist. They no longer do.

For users this changes nothing on any browser since #528: the value was
ignored. A config that still passes canvas:seed gets the usual "Skipping
unknown patch" notice instead of silence. On a browser from before #528, the
launcher no longer turns canvas noise on, which is the behaviour #528 chose.

The same audit found more keys declared in settings/properties.json that no
patch or Juggler file reads, so setting them did nothing:
- canvas:aaOffset, canvas:aaCapOffset
- memorysaver, pdfViewerEnabled, webrtc:localipv4/6
- navigator.onLine, navigator.cookieEnabled, navigator.languages
- navigator.appCodeName, appName, product, productSub. Firefox reports these
  constants itself, so fpgen.yml no longer maps them.
- webGl:parameters:blockIfNotDefined and its WebGL2 twin

test_config_schema now checks this direction too: every declared key must be
read by the browser, unless it is listed with a reason. Three are listed:
locale:script and navigator.doNotTrack, which the launcher applies itself,
and navigator.buildID (#780).

The build-tester grading followed the same wrong premise. It tracked canvas
collisions as an unfixed per-context leak. A canvas that is rendered rather
than noised follows the fonts and GPU, as it does on real machines, so canvas
collisions are now counted with the other device-level values. The tribal rule
that recorded it as an open question is now a settled one,
canvas-is-not-noised, with an automated check.

Closes #721.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(python): repair devicePixelRatio the same way on every launch

The DPR repair snaps an off-grid ratio to the nearest real scaling step and
keeps the first of two equally near steps. The steps were frozenset
literals, and a frozenset literal iterates in one order when the module is
compiled from source and another when it is loaded back from a .pyc. So a
midpoint such as 1.125 became 1.25 on the first launch after an install and
1 on every launch after it: the same pinned identity presented two different
devicePixelRatio values.

The steps are now ascending tuples, so a tie always goes to the lower step.
The test runs the repair in two fresh interpreters that share a bytecode
cache, compiling in the first and loading in the second. It failed before
this change.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix: remove the glyph-spacing seed from the browser and the launcher

anti-font-fingerprinting.patch added a seeded amount to every glyph advance,
so that text widths differed per context. No real machine produces those
widths: the same font on the same OS measures the same everywhere. So the
noise was itself a fingerprint, measured in #779 at +1 px per ~100 glyphs
plus fractional deltas on every measureText. #779 defaulted the seed to 0
and kept it as an opt-in, but an opt-in whose only effect is to become
detectable is not worth carrying. Removed:

- The browser side:
  - FontSpacingSeedManager and window.setFontSpacingSeed;
  - the HarfBuzz hook;
  - the plumbing that existed only to carry the context id down to the
    shaper: the userContextId on gfxTextRun, gfxShapedWord and the word-cache
    key, and the extra MakeTextRun argument in nsTextFrame, nsFontMetrics,
    MathML and canvas.
  The font group keeps its userContextId, which font-list-spoofing.patch
  uses to apply the per-context font list. Text is now shaped exactly as
  stock Firefox shapes it.
- The fonts:spacing_seed key. The launcher had been sending 0 on every
  launch, plus a setFontSpacingSeed(0) call in every context's init script.
- tests/patches/config-overrides.py, which tested only the spacing override.
  A pythonlib test now covers config_overrides with another key.

timezone-spoofing, webrtc-ip-spoofing and window-setter-seal change only in
context lines and the setter seal list. Every patch applies cleanly to a
fresh tree, and the result builds. The settled decision is recorded as
no-glyph-spacing-noise, with an automated check.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix: stock animations and speech by default; drop config keys that freeze live values

Three behaviours a page could detect, changed in one breaking release:

- **Animations run on stock timing.** no-css-animations.patch finished every
  finite animation at once by default, and any page could read it:
  `el.animate(frames, 1000).effect.getComputedTiming().duration` was 0, and a
  500ms transition reported 0. Measured on v152.0.4-beta.31. The speedup is
  now an opt-in, `instantAnimations: True`, which raises a LeakWarning.
  disableInstantAnimations is gone.
- **speak() on a spoofed voice works like a real voice.** It fired `error`
  after 3ms unless voices:fakeCompletion was set, and then start and end in
  the same tick. It now starts and ends after the text's duration at ~150
  words per minute. Both voices:fakeCompletion keys are gone, and so is a
  debug line printed to stderr on every call.
- **Keys removed:**
  - battery:* and window.scrollMinX/Y: Firefox keeps getBattery() and
    scrollMin* chrome-only, so no page could read them.
  - window.scrollMaxX/Y, screen.pageXOffset/pageYOffset,
    window.history.length and document.body.client*: each pinned a live value
    to a constant, so scrolling, navigating or re-laying out never changed it.
    fpgen.yml mapped pageYOffset, so about 15% of identities froze
    window.scrollY at a non-zero value.
  - The body keys' role as an undocumented alias for window.innerWidth/Height
    in browser-init and in the launcher.
  - MaskConfig::GetInt32Rect, which only the body keys used.

New guards, both of which fail on v152.0.4-beta.31:
tests/patches/animation-timing.py and tests/patches/spoofed-voice-speaks.py.
The decisions are recorded as animations-run-on-stock-timing and
spoofed-voices-speak. Every patch applies cleanly to a fresh tree, and the
result builds.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(python)!: remove dead public API and make `list all --path` work

Breaking changes:

- Remove the exceptions UnknownProperty, InvalidDebugPort and
  MissingDebugPort. Nothing in the package raises them, so code catching
  them was catching nothing.
- Remove the legacy `allow_webgl` keyword of launch_options(). Use
  `block_webgl=True`. The keyword now reaches Playwright as an unknown
  launch option and fails there instead of being silently consumed.

`camoufox list all --path` accepted the flag and ignored it. It now prints
the install path beside each installed build, as `camoufox list --path`
already does for the installed tree.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* chore(python)!: drop data the package never draws from

voices.json shipped in the wheel, but no code in the package reads it: the
voice draw uses voice-manifests.json and voice-uris.json. Its only readers
are the TypeScript port's golden-fixture generator and data-sync script
(typescript/scripts/golden/identity_golden.py,
typescript/scripts/sync-identity-data.py), which live on another branch and
will need a new source; the last copy is at
676fb3f:pythonlib/camoufox/voices.json. docs/per-context-patches.md
described it as runtime data and now describes the files that are.

webgl_data.db held two rows with zero weight on every OS ("Intel(R) HD
Graphics 400, or similar" from "Intel Inc." and "Radeon R9 200 Series, or
similar" from "ATI Technologies Inc."), left behind when their impossible
macOS weights were zeroed. No draw can reach them. They are deleted with
secure_delete so their blobs do not linger in free pages; the file is not
vacuumed, so the other pages are unchanged. A new test requires every row
to be drawable on at least one OS.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(python): warn whenever an identity falls back to a substitute value

Several draws swallowed their failure and used something else, so an
identity could ship with values the rest of it was not drawn to match and
nobody would hear about it:

- from_preset(): a failed font or voice draw used the preset's recorded
  list, or nothing, on any exception.
- generate_context_fingerprint(): a failed font, voice or WebGL draw was
  `except Exception: pass`, leaving the browser's launch-time values.
- _load_font_groups() / _load_font_bases(): an unreadable file became {},
  i.e. no font additions or no OS-version base.
- launch_options(): a failed font draw used every font in fonts.json, a
  failed voice draw used no voices, and a preset GPU missing from
  webgl_data.db was silently swapped for a drawn one (36 of the 397
  bundled presets).

Each site now catches only the errors its data can raise (OSError and
ValueError for an unreadable or corrupt file, KeyError for a manifest with
no entry for the OS, sqlite3.Error for the WebGL database) and emits a
FallbackWarning. The text names what failed and what the identity uses
instead, then gives a block to paste into an issue (camoufox, browser, OS
and Python versions, the error, and the identity's user agent or GPU),
asking the user to report it on GitHub. It shares LeakWarning's
caller-frame attribution and its template lives in warnings.yml.

The broad excepts had also been hiding a broken fixture:
test_launch_environment's font and voice stubs did not accept `seed`, so
every draw there raised and was swallowed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(python): give NewContext identities the browser's Firefox version

NewContext() and AsyncNewContext() passed ff_version=None through to
generate_context_fingerprint(), so a context's user agent kept the version
fpgen drew (e.g. Firefox/146) while the browser underneath was 152. They
now default ff_version to the major version of Playwright's
Browser.version, which Juggler reports from MOZ_APP_VERSION_DISPLAY, so the
UA always names the browser the page is actually talking to. An explicit
ff_version still wins.

The docstrings said each context gets "its own real fingerprint preset";
the default has been an fpgen draw, with a preset only when one is passed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(python): send an IPv6 WebRTC address to setWebRTCIPv6

The per-context init script passed every webrtc_ip, IPv6 included, to
window.setWebRTCIPv4(), and never called setWebRTCIPv6(). An IPv6 address
(given directly, or resolved as a proxy's exit IP) was stored as the
context's IPv4 value and the IPv6 slot stayed empty. The script now picks
the setter by address family, and an address that is neither raises
InvalidIP instead of being passed through.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(python): stop pinning the page's scroll offset from fpgen

fpgen.yml mapped the drawn window.pageYOffset (e.g. 528) to
screen.pageYOffset, and the browser returns that value from scrollY on
every read, so a page saw one scroll position forever whatever the user
did. Real scroll offsets are live page state, not part of a device's
fingerprint, so neither offset is mapped any more.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* chore(python): stop checking a config key that no longer exists

warn_manual_config() looked for navigator.languages, which was removed
from settings/properties.json; validate_config() rejects it before the
check could matter.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(python): close the WebGL database connection on every path

sample_webgl raised its not-found and wrong-OS errors before reaching
conn.close(), leaking a sqlite connection each time a preset named a GPU the
database does not hold.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* chore(data): drop the 23 presets whose GPU has no WebGL data

A preset records only its GPU's name. The WebGL parameters, extensions and
shader precision behind it have to come from somewhere, and for these 23
nothing Camoufox has describes the GPU: fpgen has never seen Firefox report it
on that OS. So each launch paired the name with another device's parameters,
a mismatch any WebGL fingerprinter can see. They were:

- Windows on ARM (Adreno 650);
- Direct3D 10-level GPUs (vs_4_0/vs_4_1);
- "Generic Renderer";
- 945GM and GTX 480 on macOS;
- nouveau/Mesa buckets on Linux;
- one Linux preset pairing NVIDIA's proprietary vendor string with the
  nouveau renderer name.

scripts/clean-fingerprint-data.py now applies the rule, via a shared
fingerprints.firefox_gpus(), and test_shipped_data asserts it. 374 presets
remain, and every OS keeps its presets. ROADMAP.md lists capturing WebGL data
for these GPUs, which would bring them back.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* feat(python): draw every identity's WebGL from fpgen

WebGL vendor, renderer, context attributes, extensions, parameters and
shader precisions, for WebGL1 and WebGL2, now come from fpgen's recorded
Firefox devices instead of webgl_data.db, which is deleted with the
camoufox/webgl/ package.

camoufox/webgl.py:
- webgl_for_gpu() traces `webgl` given Firefox, the OS and the GPU, then
  `webgl2` given the chosen `webgl` too, and draws each with one seeded
  random.Random. The GPU and the webgl value are pinned by their fpgen
  lookup index: a dict condition is flattened into leaves that overwrite
  each other, so only the renderer applied and Linux "Mesa" and "AMD"
  Radeon HD 3200 devices came back mixed.
- sample_webgl_for_screen() draws the GPU of a generated identity from
  fpgen's per-OS weights, filtering out software rasterisers, GPUs the OS
  cannot report, discrete GPUs behind a netbook screen and the
  resistFingerprinting "Mozilla" mask before the weighted choice, so there
  is no rejection loop. An empty pool raises.
- The draft/host-dependent extension filter moves over unchanged.

A preset's GPU and a caller's webgl_config pair are looked up as given;
a pair fpgen has never seen from Firefox on that OS raises instead of
falling back to another GPU. generate_context_fingerprint no longer
falls back to the host GPU when the draw fails.

For 10 of the 15 (GPU, OS) pairs the two sources share, one of fpgen's
records converts to exactly the database row on every value the browser
reads. The other five rows (Linux R9 200 and Radeon HD 3200, macOS
Intel HD, and two software rasterisers) are devices fpgen does not carry;
those GPUs now present fpgen's recorded devices instead. The Linux
GTX 980 row is kept as a test fixture.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* docs: say where WebGL comes from now that the database is gone

The per-context guide, the fpgen.yml header and coherence's comments still
named webgl_data.db and sample_webgl(). They now point at camoufox/webgl.py
and fpgen. The guide also claimed presets carry WebGL parameters; they
record only the vendor and renderer.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(patches): a host's missing speech daemon no longer errors spoofed speech

On a Linux host where speech-dispatcher cannot start, Firefox broadcasts
synth-voices-error, and SpeechSynthesis answers it by firing `error` on every
queued utterance. So a spoofed Windows voice errored about 11ms into speak()
on any host without the daemon: the CI runners, and most servers. It passed
only where the daemon runs.

While Camoufox manages the voice list, the registry no longer forwards a host
backend's error. The spoofed voices do not depend on the host's engine, and a
Windows or macOS identity never raises one. The guard now makes the daemon
unreachable itself, so it tests this case on every machine; on the previous
build it fails every time.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* ci: stop skipping the two click tests that stock animation timing fixed

test_wait_for_stable_position and test_timeout_waiting_for_stable_position
were skipped with humanized travel time as the reason. The real cause was
instant animations. Every finite animation finished at once, so the button
Playwright waits on to stop moving never moved, and the click landed where
upstream does not expect. With animations on stock timing both pass, and the
skiplist audit flagged them as no longer failing. The entries go, and the
counts in ci/README.md drop from 14 to 12.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(build-tester): accept 18 and 22 cores, as real hardware reports

plausibleHWC's list of common core counts lacked 18 and 22 -- Intel Meteor
Lake laptops (Core Ultra 5 125H, Core Ultra 7 155H), and 22 is in 8 recorded
presets. build-tester draws random presets, so a run that picked one of the two
Linux presets reporting 22 failed: about one run in eleven, on any pull
request. A CI self-test now fails if the list rejects any core count pythonlib
can present (the presets and PLAUSIBLE_CORE_COUNTS).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* test(guards): judge the query-cost probes on a median, not one sample

stock-parity-probes timed each getter once. On a shared runner one GC pause or
CPU-steal spike decided the verdict: navigator.hardwareConcurrency took 77 ms
against a 50 ms allowance on the same restored build that passed the run
before. Each pair is now timed five times, interleaved, and compared by median.
The regressions these catch (a sync IPC per read, ~240 ms over the loop) cost
extra on every read, so they move the median; verified by giving the getter a
constant ~4 us of extra work per read -- 86 ms median, FAIL -- while the
healthy build passes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* test(native): compare the whole fingerprint when two launches must differ

test_two_browsers_get_different_fingerprints compared seven coarse values:
UA, platform, screen size, core count, timezone and language. CI pins the
timezone and language, and real machines share the rest: two draws of a
common Mac (Firefox 152, MacIntel, 2560x1440, 8 cores) matched, and the test
failed on a correct browser.

It now reads the whole fingerprint a site computes, from a script in the page:
- navigator values, screen and window geometry, device pixel ratio, timezone;
- WebGL vendor, renderer, limits and extensions;
- installed fonts, measured by width against the generic fallbacks;
- voices, media-device counts, and an OfflineAudioContext hash.
The page is served from an https URL Playwright fulfils locally, because
mediaDevices exists only in a secure context. The page computes the result
itself because the isolated world may not read audio sample data. The test
then requires the fingerprints to differ, and the audio hash to differ on its
own, since its noise is seeded per identity.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Update README to remove warning, camoufox is now actively maintained

Camoufox will now be actively maintained and improved for the foreseeable future

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-09-26 20:13:35 +00:00

391 lines
16 KiB
Python

"""Regression tests for per-launch environment isolation."""
import os
import pytest
from camoufox import utils
@pytest.fixture
def isolated_launch_dependencies(monkeypatch):
"""Keep launch_options focused on environment assembly, without a browser."""
monkeypatch.setattr(utils, "add_default_addons", lambda *args, **kwargs: None)
monkeypatch.setattr(utils, "generate_fingerprint", lambda *args, **kwargs: object())
monkeypatch.setattr(utils, "from_fpgen", lambda *args, **kwargs: {})
monkeypatch.setattr(utils, "get_screen_cons", lambda *args, **kwargs: None)
monkeypatch.setattr(utils, "_generate_random_font_subset", lambda *args, **kwargs: [])
monkeypatch.setattr(utils, "_generate_random_voice_subset", lambda *args, **kwargs: [])
monkeypatch.setattr(utils, "fix_navigator_arch", lambda *args: None)
monkeypatch.setattr(utils, "fix_screen_no_taskbar", lambda *args: None)
monkeypatch.setattr(utils, "clamp_window_dimensions", lambda *args: None)
monkeypatch.setattr(utils, "set_media_devices_defaults", lambda *args: None)
monkeypatch.setattr(utils, "installed_verstr", lambda: "152.0.4-beta.28")
monkeypatch.setattr(utils, "validate_config", lambda *args, **kwargs: None)
monkeypatch.setattr(utils, "get_env_vars", lambda *args, **kwargs: {})
monkeypatch.setattr(utils, "launch_path", lambda: "/test/camoufox")
def _launch_with_virtual_display(**kwargs):
return utils.launch_options(
virtual_display=":4242",
headless=True,
block_webgl=True,
i_know_what_im_doing=True,
**kwargs,
)
def test_virtual_display_does_not_mutate_process_environment(
monkeypatch, isolated_launch_dependencies
):
monkeypatch.delenv("DISPLAY", raising=False)
monkeypatch.setenv("GDK_BACKEND", "wayland")
monkeypatch.setenv("WAYLAND_DISPLAY", "wayland-0")
monkeypatch.setenv("MOZ_ENABLE_WAYLAND", "1")
keys = ("DISPLAY", "GDK_BACKEND", "WAYLAND_DISPLAY", "MOZ_ENABLE_WAYLAND")
before = {key: os.environ.get(key) for key in keys}
options = _launch_with_virtual_display()
assert {key: os.environ.get(key) for key in keys} == before
assert options["env"]["DISPLAY"] == ":4242"
assert options["env"]["GDK_BACKEND"] == "x11"
assert "WAYLAND_DISPLAY" not in options["env"]
assert options["env"]["MOZ_ENABLE_WAYLAND"] == "0"
def test_virtual_display_does_not_mutate_caller_environment(
isolated_launch_dependencies,
):
caller_env = {
"UNCHANGED": "value",
"GDK_BACKEND": "wayland",
"WAYLAND_DISPLAY": "wayland-0",
"MOZ_ENABLE_WAYLAND": "1",
}
before = caller_env.copy()
options = _launch_with_virtual_display(env=caller_env)
assert caller_env == before
assert options["env"]["UNCHANGED"] == "value"
assert options["env"]["DISPLAY"] == ":4242"
assert options["env"]["GDK_BACKEND"] == "x11"
assert "WAYLAND_DISPLAY" not in options["env"]
assert options["env"]["MOZ_ENABLE_WAYLAND"] == "0"
class TestFontFallbackAsyncPref:
"""Per-character font fallback must not skip families whose
charmap is not loaded yet.
Gecko's GlobalFontFallback walks the shared font list for a family covering
the character; in a content process with async fallback on it hits the
`!family.IsFullyInitialized()` branch, schedules a cmap load and SKIPS the
family, so the first measurement of a character only one bundled family
provides returns the primary family's .notdef. Linux takes that path for
every fallback (UseCmapsDuringSystemFallback), so the font-hijacker change
that restored this on macOS cannot reach it there.
macOS must NOT get the pref: it uses the CoreText fallback, and forcing the
synchronous scan changed the face picked for U+1E9E in Futura (stock 21.733
-> 27.267), measured on a real Mac mini.
"""
PREF = "gfx.font_rendering.fallback.async"
def _prefs_for(self, ua, isolated):
return utils.launch_options(
config={"navigator.userAgent": ua},
i_know_what_im_doing=True,
)["firefox_user_prefs"]
def test_linux_disables_async_font_fallback(self, isolated_launch_dependencies):
prefs = self._prefs_for("Mozilla/5.0 (X11; Linux x86_64; rv:152.0) Gecko/20100101 Firefox/152.0", None)
assert prefs[self.PREF] is False
def test_macos_keeps_async_font_fallback(self, isolated_launch_dependencies):
prefs = self._prefs_for(
"Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:152.0) Gecko/20100101 Firefox/152.0", None
)
assert self.PREF not in prefs
def test_windows_keeps_async_font_fallback(self, isolated_launch_dependencies):
prefs = self._prefs_for(
"Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:152.0) Gecko/20100101 Firefox/152.0", None
)
assert self.PREF not in prefs
def test_caller_pref_wins(self, isolated_launch_dependencies):
prefs = utils.launch_options(
config={"navigator.userAgent": "Mozilla/5.0 (X11; Linux x86_64; rv:152.0) Gecko/20100101 Firefox/152.0"},
firefox_user_prefs={"gfx.font_rendering.fallback.async": True},
i_know_what_im_doing=True,
)["firefox_user_prefs"]
assert prefs[self.PREF] is True
class TestUiLocaleFollowsIntlLocale:
"""The packaged browser locale must follow the spoofed Intl locale.
With locale="fr-FR" and the browser left on en-US, Intl formatting went
French while input.validationMessage and XML parse errors stayed English --
a mix no real Firefox produces. Packages now bake in the language packs;
intl.locale.requested selects one, and must always be set because an empty
value would follow the host OS locale.
"""
PREF = "intl.locale.requested"
UA = "Mozilla/5.0 (X11; Linux x86_64; rv:152.0) Gecko/20100101 Firefox/152.0"
def _prefs(self, **kwargs):
return utils.launch_options(
config={"navigator.userAgent": self.UA, **kwargs.pop("config", {})},
i_know_what_im_doing=True,
**kwargs,
)["firefox_user_prefs"]
def test_default_identity_pins_en_us(self, isolated_launch_dependencies):
assert self._prefs()[self.PREF] == "en-US"
def test_spoofed_locale_selects_matching_ui_locale(self, isolated_launch_dependencies):
# handle_locale adds the likely script; Gecko's filtering negotiation
# treats a packaged "fr" as a range, so fr-Latn-FR still selects fr.
assert self._prefs(locale="fr-FR")[self.PREF] == "fr-Latn-FR"
assert self._prefs(locale="pt-BR")[self.PREF] == "pt-Latn-BR"
def test_first_of_several_locales_wins(self, isolated_launch_dependencies):
assert self._prefs(locale="de-DE, en-US")[self.PREF] == "de-Latn-DE"
def test_geoip_style_config_locale_is_used(self, isolated_launch_dependencies):
config = {"locale:language": "ja", "locale:region": "JP"}
assert self._prefs(config=config)[self.PREF] == "ja-JP"
def test_script_subtag_is_kept(self, isolated_launch_dependencies):
config = {"locale:language": "zh", "locale:script": "Hant", "locale:region": "TW"}
assert self._prefs(config=config)[self.PREF] == "zh-Hant-TW"
def test_caller_pref_wins(self, isolated_launch_dependencies):
prefs = self._prefs(locale="fr-FR", firefox_user_prefs={self.PREF: "de"})
assert prefs[self.PREF] == "de"
class TestPrefsReachStartup:
"""Launcher prefs must be readable by camoufox.cfg at startup.
Playwright's non-persistent launch writes no user.js, so firefox_user_prefs
only arrived via juggler after startup; intl.locale.requested lost the race
against Gecko's pre-created string bundles on Windows.
"""
UA = "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:152.0) Gecko/20100101 Firefox/152.0"
def test_prefs_are_passed_as_env(self, isolated_launch_dependencies):
import orjson
opts = utils.launch_options(config={"navigator.userAgent": self.UA}, locale="fr-FR", i_know_what_im_doing=True)
chunks = sorted((k for k in opts["env"] if k.startswith("CAMOU_PREFS_")), key=lambda k: int(k.rsplit("_", 1)[1]))
assert chunks and chunks[0] == "CAMOU_PREFS_1"
prefs = orjson.loads("".join(opts["env"][k] for k in chunks))
assert prefs == opts["firefox_user_prefs"]
assert prefs["intl.locale.requested"] == "fr-Latn-FR"
def test_large_prefs_are_chunked_in_order(self, monkeypatch):
import orjson
monkeypatch.setattr(utils, "OS_NAME", "win")
prefs = {f"camoufox.test.pref{i}": "x" * 50 for i in range(200)}
env = utils.get_pref_env_vars(prefs)
assert len(env) > 1 and all(len(v) <= 2047 for v in env.values())
joined = "".join(env[f"CAMOU_PREFS_{i}"] for i in range(1, len(env) + 1))
assert orjson.loads(joined) == prefs
def test_no_prefs_no_env(self):
assert utils.get_pref_env_vars({}) == {}
class TestWindowsScrollbarsFollowVersion:
"""Windows 11 draws overlay scrollbars by default (stock 152.0.4 on Win11: 0 px),
Windows 10 classic 17 px ones; the identity's font draw decides the version."""
PREF = "ui.useOverlayScrollbars"
WIN_UA = "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:152.0) Gecko/20100101 Firefox/152.0"
def _prefs(self, fonts, ua=None):
return utils.launch_options(
config={"navigator.userAgent": ua or self.WIN_UA, "fonts": fonts},
i_know_what_im_doing=True,
)["firefox_user_prefs"]
def test_windows_11_fonts_get_overlay(self, isolated_launch_dependencies):
assert self._prefs(["Arial", "Segoe UI Variable Text"])[self.PREF] == 1
def test_windows_10_fonts_get_classic(self, isolated_launch_dependencies):
assert self._prefs(["Arial", "Segoe UI", "Calibri"])[self.PREF] == 0
def test_other_oses_overlay(self, isolated_launch_dependencies):
ua = "Mozilla/5.0 (X11; Linux x86_64; rv:152.0) Gecko/20100101 Firefox/152.0"
assert self._prefs(["DejaVu Sans"], ua=ua)[self.PREF] == 1
def test_marker_set_is_the_font_model(self):
from camoufox.fingerprints import _BASE_VARIANT_FONTS_WINDOWS, WINDOWS_11_MARKER_FONTS
assert WINDOWS_11_MARKER_FONTS == frozenset(_BASE_VARIANT_FONTS_WINDOWS[1])
class TestNativeWindowsVariantFonts:
"""A native Windows identity claims the Win11 font variant iff the host has it."""
def test_native_windows_11_host_claims_variant(self, monkeypatch):
from camoufox import fingerprints as fp
monkeypatch.setattr(fp, "_host_has_variant_fonts", lambda target_os: True)
fonts = fp._generate_random_font_subset("windows", seed=1, native=True)
assert fp.WINDOWS_11_MARKER_FONTS <= set(fonts)
def test_native_windows_10_host_does_not(self, monkeypatch):
from camoufox import fingerprints as fp
monkeypatch.setattr(fp, "_host_has_variant_fonts", lambda target_os: False)
fonts = fp._generate_random_font_subset("windows", seed=1, native=True)
assert not (fp.WINDOWS_11_MARKER_FONTS & set(fonts))
def test_non_windows_hosts_never_report_variant(self):
from camoufox import fingerprints as fp
assert fp._host_has_variant_fonts("linux") is False
assert fp._host_has_variant_fonts("macos") is False
class _Usage:
"""shutil.disk_usage's namedtuple, with only `total` filled in."""
def __init__(self, total):
self.total = total
self.used = 0
self.free = total
class TestStorageQuotaFollowsHostDisk:
"""The storage quota a page reads must be the host's, not a constant.
Gecko derives navigator.storage.estimate().quota from the disk: the
temporary-storage limit is GetDiskCapacity() / 2 and the group limit a page
reads is min(that / 5, 10 GiB). camoufox.cfg used to pin the limit to
52428800 KB -- 50 GiB, which is exactly nsRFPService::GetSpoofedStorageLimit()
and reports 10 GiB on every host whatever its disk holds.
Deriving it from the host keeps the shape Gecko produces (a 100 GB+ disk
reports the 10 GiB cap, a smaller one reports capacity / 10) while ignoring
the disk Playwright's throwaway profile happens to land on -- a tmpfs /tmp
is a RAM-sized volume no real profile lives on.
"""
PREF = "dom.quotaManager.temporaryStorage.fixedLimit"
UA = "Mozilla/5.0 (X11; Linux x86_64; rv:152.0) Gecko/20100101 Firefox/152.0"
def _prefs(self, **kwargs):
return utils.launch_options(
config={"navigator.userAgent": self.UA},
i_know_what_im_doing=True,
**kwargs,
)["firefox_user_prefs"]
def test_limit_is_half_the_host_disk(self, monkeypatch, isolated_launch_dependencies):
# 512 GiB, the way a filesystem reports it: a multiple of the block size.
capacity = 512 * 1024**3
monkeypatch.setattr(utils.shutil, "disk_usage", lambda _p: _Usage(capacity))
assert self._prefs()[self.PREF] == capacity // 2 // 1024
def test_small_disk_reports_less_than_the_cap(
self, monkeypatch, isolated_launch_dependencies
):
# A 40 GB VPS: stock reports 4 GB, not the 10 GiB cap. The old pin
# claimed 10 GiB here, which that machine's own Firefox never says.
capacity = 40 * 1000**3
monkeypatch.setattr(utils.shutil, "disk_usage", lambda _p: _Usage(capacity))
limit_kb = self._prefs()[self.PREF]
group_limit = min(limit_kb * 1024 // 5, 10 * 1024**3)
assert group_limit == capacity // 2 // 5
assert group_limit < 10 * 1024**3
def test_multi_terabyte_disk_stays_in_int32(
self, monkeypatch, isolated_launch_dependencies
):
monkeypatch.setattr(utils.shutil, "disk_usage", lambda _p: _Usage(16 * 1024**4))
limit_kb = self._prefs()[self.PREF]
assert limit_kb <= 2**31 - 1
# Still above 50 GiB, so the page reads the same 10 GiB cap stock does.
assert limit_kb * 1024 // 5 >= 10 * 1024**3
def test_unreadable_disk_leaves_gecko_to_measure(
self, monkeypatch, isolated_launch_dependencies
):
def _raise(_p):
raise OSError("no such device")
monkeypatch.setattr(utils.shutil, "disk_usage", _raise)
assert self.PREF not in self._prefs()
def test_caller_pref_wins(self, monkeypatch, isolated_launch_dependencies):
monkeypatch.setattr(utils.shutil, "disk_usage", lambda _p: _Usage(512 * 1024**3))
prefs = self._prefs(firefox_user_prefs={self.PREF: 1234})
assert prefs[self.PREF] == 1234
class TestStockMediaDefaults:
"""The host's own media features, not Playwright's emulated ones.
Playwright emulates four media features on every context whether or not the
caller asked: colorScheme "light", and no-preference values for
reducedMotion / forcedColors / contrast. The page then reads those whatever
the machine is set to -- measured 2026-09-18, headed on an Xvfb with
GTK_THEME=Adwaita:dark: stock Firefox reported
`(prefers-color-scheme: dark)`, camoufox reported light.
"no-override" is Playwright's opt-out: no emulation is sent and the browser
answers from the host.
"""
def test_defaults_are_no_override(self):
assert utils.STOCK_MEDIA_DEFAULTS == {
"color_scheme": "no-override",
"reduced_motion": "no-override",
"forced_colors": "no-override",
"contrast": "no-override",
}
def test_new_page_and_new_context_get_them(self):
class FakeBrowser:
def __init__(self):
self.calls = []
def new_page(self, **kwargs):
self.calls.append(("new_page", kwargs))
def new_context(self, **kwargs):
self.calls.append(("new_context", kwargs))
browser = FakeBrowser()
utils.attach_stock_media_defaults(browser)
browser.new_page()
browser.new_context()
for _, kwargs in browser.calls:
assert kwargs["color_scheme"] == "no-override"
assert kwargs["reduced_motion"] == "no-override"
assert kwargs["forced_colors"] == "no-override"
assert kwargs["contrast"] == "no-override"
def test_caller_value_wins(self):
class FakeBrowser:
def __init__(self):
self.kwargs = None
def new_context(self, **kwargs):
self.kwargs = kwargs
browser = FakeBrowser()
utils.attach_stock_media_defaults(browser)
browser.new_context(color_scheme="dark", forced_colors="active")
assert browser.kwargs["color_scheme"] == "dark"
assert browser.kwargs["forced_colors"] == "active"
# the ones the caller left alone still follow the host
assert browser.kwargs["reduced_motion"] == "no-override"