# kkapsner/CanvasBlocker

A Firefox extension to protect from being fingerprinted.

Repository: https://github.com/kkapsner/CanvasBlocker
Canonical: https://ross.abutalabs.com/products/canvasblocker
Homepage: https://canvasblocker.kkapsner.de
Language: JavaScript
License: MPL-2.0
License Family: copyleft
Topics: web-extension, privacy, firefox, fingerprinting
Last push: 2026-02-20T13:38:11+00:00

## Health v2 (maintenance only)
Score: 64/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 68, release rhythm 38, longevity 100
- inputs: {"age_days": 4417, "days_push": 194, "days_rel": 201, "gap_med": 393, "n_releases_24m": 2}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1501, forks 94 (observed 2026-08-28T04:04:54.354398+00:00)

## What it is
A Firefox browser extension that protects users from browser fingerprinting by blocking or faking readouts of JavaScript APIs such as canvas, WebGL, audio, and navigator. It offers multiple block modes including faking values, whitelists, blacklists, and per-site permission prompts.

## Use cases
- prevent websites from fingerprinting my browser
- block canvas fingerprinting in firefox
- fake webgl and audio fingerprint readouts
- protect against browser tracking without breaking all sites
- whitelist trusted sites while blocking fingerprinting elsewhere

## When to choose
- you use Firefox and want fine-grained control over fingerprinting APIs
- you prefer faking readouts over fully blocking APIs to keep sites working
- you need per-site whitelist/blacklist behavior

## When to avoid
- you use Chrome or another non-WebExtension-compatible browser
- you want a set-and-forget solution without configuration
- you already run another fingerprinting protection for the same APIs, which can cause conflicts

## Facets
- artifact type: plugin
- maturity: active
- function: privacy, security
- domain: privacy, browser-extensions, security
- platform: browser, browser-extension
- tags: fingerprinting, firefox, anti-tracking, webextension, canvas

## Member repositories
- kkapsner/CanvasBlocker (main) score 64

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:54.354398+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T04:32:56.616982+00:00, confidence not recorded.
  - readme: https://github.com/kkapsner/CanvasBlocker (fetched 2026-08-28T04:04:54.354398+00:00, sha f7bed16a3eea)
  - homepage: https://canvasblocker.kkapsner.de (fetched 2026-08-29T11:38:11.032900+00:00, sha 78b22d5c0c8c)
  - site_page: https://canvasblocker.kkapsner.de/faq (fetched 2026-08-29T11:38:11.041729+00:00, sha 0aa2086ca4d7)
- Data as of 2026-08-30T08:39:29.467469+00:00.