/****** * name: arkenfox user.js * date: 5 February 2024 * version: 122 * urls: https://github.com/arkenfox/user.js [repo] * : https://arkenfox.github.io/gui/ [interactive] * license: MIT: https://github.com/arkenfox/user.js/blob/master/LICENSE.txt * README: 1. Consider using Tor Browser if it meets your needs or fits your threat model * https://2019.www.torproject.org/about/torusers.html 2. Read the entire wiki * https://github.com/arkenfox/user.js/wiki 3. If you skipped step 2, return to step 2 4. Make changes in a user-overrides.js * There are often trade-offs and conflicts between security vs privacy vs anti-tracking and these need to be balanced against functionality & convenience & breakage * Some site breakage and unintended consequences will happen. Everyone's experience will differ e.g. some user data is erased on exit (section 2800), change this to suit your needs * While not 100% definitive, search for "[SETUP" tags 5. Some tag info [SETUP-SECURITY] it's one item, read it [SETUP-WEB] can cause some websites to break [SETUP-CHROME] changes how Firefox itself behaves (i.e. not directly website related) 6. Override Recipes: https://github.com/arkenfox/user.js/issues/1080 * RELEASES: https://github.com/arkenfox/user.js/releases * Use the arkenfox release that matches your Firefox version - DON'T wait for arkenfox to update Firefox, nothing major changes these days * Each release - run prefsCleaner to reset prefs made inactive, including deprecated (9999) * ESR - It is recommended to not use the updater, or you will get a later version which may cause issues. So you should manually append your overrides (and keep a copy), and manually update when you change ESR releases (arkenfox is already past that release) - If you decide to keep updating, then the onus is on - also see section 9999 * INDEX: 0100: STARTUP 0200: GEOLOCATION 0300: QUIETER FOX 0400: SAFE BROWSING 0600: BLOCK IMPLICIT OUTBOUND 0700: DNS / DoH / PROXY / SOCKS 0800: LOCATION BAR / SEARCH BAR / SUGGESTIONS / HISTORY / FORMS 0900: PASSWORDS 1000: DISK AVOIDANCE 1200: HTTPS (SSL/TLS / OCSP / CERTS / HPKP) 1700: CONTAINERS 2000: PLUGINS / MEDIA / WEBRTC 2400: DOM (DOCUMENT OBJECT MODEL) 2600: MISCELLANEOUS 2700: ETP (ENHANCED TRACKING PROTECTION) 2800: SHUTDOWN & SANITIZING 4000: FPP (fingerprintingProtection) 5000: OPTIONAL OPSEC 5500: OPTIONAL HARDENING 6000: DON'T TOUCH 7000: DON'T BOTHER 8000: DON'T BOTHER: FINGERPRINTING 9000: NON-PROJECT RELATED 9999: DEPRECATED / RENAMED ******/ /* START: internal custom pref to test for syntax errors * [NOTE] Not all syntax errors cause parsing to abort i.e. reaching the last debug pref * no longer necessarily means that all prefs have been applied. Check the console right * after startup for any warnings/error messages related to non-applied prefs * [1] https://blog.mozilla.org/nnethercote/2018/03/09/a-new-preferences-parser-for-firefox/ ***/ user_pref("_user.js.parrot", "START: Oh yes, the Norwegian Blue... what's wrong with it?"); /* 0000: disable about:config warning ***/ user_pref("browser.aboutConfig.showWarning", false); /*** [SECTION 0100]: STARTUP ***/ user_pref("_user.js.parrot", "0100 syntax error: the parrot's dead!"); /* 0102: set startup page [SETUP-CHROME] * 0=blank, 1=home, 2=last visited page, 3=resume previous session * [NOTE] Session Restore is cleared with history (2811), and not used in Private Browsing mode * [SETTING] General>Startup>Restore previous session ***/ user_pref("browser.startup.page", 3); /* 0103: set HOME+NEWWINDOW page * about:home=Firefox Home (default, see 0105), custom URL, about:blank * [SETTING] Home>New Windows and Tabs>Homepage and new windows ***/ user_pref("browser.startup.homepage", "about:blank"); /* 0104: set NEWTAB page * true=Firefox Home (default, see 0105), false=blank page * [SETTING] Home>New Windows and Tabs>New tabs ***/ user_pref("browser.newtabpage.enabled", false); /* 0105: disable sponsored content on Firefox Home (Activity Stream) * [SETTING] Home>Firefox Home Content ***/ user_pref("browser.newtabpage.activity-stream.showSponsored", false); // [FF58+] Pocket > Sponsored Stories user_pref("browser.newtabpage.activity-stream.showSponsoredTopSites", false); // [FF83+] Sponsored shortcuts /* 0106: clear default topsites * [NOTE] This does not block you from adding your own ***/ user_pref("browser.newtabpage.activity-stream.default.sites", ""); /*** [SECTION 0200]: GEOLOCATION ***/ user_pref("_user.js.parrot", "0200 syntax error: the parrot's definitely deceased!"); /* 0201: use Mozilla geolocation service instead of Google if permission is granted [FF74+] * Optionally enable logging to the console (defaults to false) ***/ user_pref("geo.provider.network.url", "https://location.services.mozilla.com/v1/geolocate?key=%MOZILLA_API_KEY%"); // user_pref("geo.provider.network.logging.enabled", true); // [HIDDEN PREF] /* 0202: disable using the OS's geolocation service ***/ user_pref("geo.provider.ms-windows-location", false); // [WINDOWS] user_pref("geo.provider.use_corelocation", false); // [MAC] user_pref("geo.provider.use_gpsd", false); // [LINUX] [HIDDEN PREF] user_pref("geo.provider.use_geoclue", false); // [FF102+] [LINUX] /*** [SECTION 0300]: QUIETER FOX ***/ user_pref("_user.js.parrot", "0300 syntax error: the parrot's not pinin' for the fjords!"); /** RECOMMENDATIONS ***/ /* 0320: disable recommendation pane in about:addons (uses Google Analytics) ***/ user_pref("extensions.getAddons.showPane", false); // [HIDDEN PREF] /* 0321: disable recommendations in about:addons' Extensions and Themes panes [FF68+] ***/ user_pref("extensions.htmlaboutaddons.recommendations.enabled", false); /* 0322: disable personalized Extension Recommendations in about:addons and AMO [FF65+] * [NOTE] This pref has no effect when Health Reports (0331) are disabled * [SETTING] Privacy & Security>Firefox Data Collection & Use>Allow Firefox to make personalized extension recommendations * [1] https://support.mozilla.org/kb/personalized-extension-recommendations ***/ user_pref("browser.discovery.enabled", false); /* 0323: disable shopping experience [FF116+] * [1] https://bugzilla.mozilla.org/show_bug.cgi?id=1840156#c0 ***/ user_pref("browser.shopping.experience2023.enabled", false); // [DEFAULT: false] /** TELEMETRY ***/ /* 0330: disable new data submission [FF41+] * If disabled, no policy is shown or upload takes place, ever * [1] https://bugzilla.mozilla.org/1195552 ***/ user_pref("datareporting.policy.dataSubmissionEnabled", false); /* 0331: disable Health Reports * [SETTING] Privacy & Security>Firefox Data Collection & Use>Allow Firefox to send technical... data ***/ user_pref("datareporting.healthreport.uploadEnabled", false); /* 0332: disable telemetry * The "unified" pref affects the behavior of the "enabled" pref * - If "unified" is false then "enabled" controls the telemetry module * - If "unified" is true then "enabled" only controls whether to record extended data * [NOTE] "toolkit.telemetry.enabled" is now LOCKED to reflect prerelease (true) or release builds (false) [2] * [1] https://firefox-source-docs.mozilla.org/toolkit/components/telemetry/telemetry/internals/preferences.html * [2] https://medium.com/georg-fritzsche/data-preference-changes-in-firefox-58-2d5df9c428b5 ***/ user_pref("toolkit.telemetry.unified", false); user_pref("toolkit.telemetry.enabled", false); // see [NOTE] user_pref("toolkit.telemetry.server", "data:,"); user_pref("toolkit.telemetry.archive.enabled", false); user_pref("toolkit.telemetry.newProfilePing.enabled", false); // [FF55+] user_pref("toolkit.telemetry.shutdownPingSender.enabled", false); // [FF55+] user_pref("toolkit.telemetry.updatePing.enabled", false); // [FF56+] user_pref("toolkit.telemetry.bhrPing.enabled", false); // [FF57+] Background Hang Reporter user_pref("toolkit.telemetry.firstShutdownPing.enabled", false); // [FF57+] /* 0333: disable Telemetry Coverage * [1] https://blog.mozilla.org/data/2018/08/20/effectively-measuring-search-in-firefox/ ***/ user_pref("toolkit.telemetry.coverage.opt-out", true); // [HIDDEN PREF] user_pref("toolkit.coverage.opt-out", true); // [FF64+] [HIDDEN PREF] user_pref("toolkit.coverage.endpoint.base", ""); /* 0334: disable PingCentre telemetry (used in several System Add-ons) [FF57+] * Defense-in-depth: currently covered by 0331 ***/ user_pref("browser.ping-centre.telemetry", false); /* 0335: disable Firefox Home (Activity Stream) telemetry ***/ user_pref("browser.newtabpage.activity-stream.feeds.telemetry", false); user_pref("browser.newtabpage.activity-stream.telemetry", false); /** STUDIES ***/ /* 0340: disable Studies * [SETTING] Privacy & Security>Firefox Data Collection & Use>Allow Firefox to install and run studies ***/ user_pref("app.shield.optoutstudies.enabled", false); /* 0341: disable Normandy/Shield [FF60+] * Shield is a telemetry system that can push and test "recipes" * [1] https://mozilla.github.io/normandy/ ***/ user_pref("app.normandy.enabled", false); user_pref("app.normandy.api_url", ""); /** CRASH REPORTS ***/ /* 0350: disable Crash Reports ***/ user_pref("breakpad.reportURL", ""); user_pref("browser.tabs.crashReporting.sendReport", false); // [FF44+] // user_pref("browser.crashReports.unsubmittedCheck.enabled", false); // [FF51+] [DEFAULT: false] /* 0351: enforce no submission of backlogged Crash Reports [FF58+] * [SETTING] Privacy & Security>Firefox Data Collection & Use>Allow Firefox to send backlogged crash reports ***/ user_pref("browser.crashReports.unsubmittedCheck.autoSubmit2", false); // [DEFAULT: false] /** OTHER ***/ /* 0360: disable Captive Portal detection * [1] https://www.eff.org/deeplinks/2017/08/how-captive-portals-interfere-wireless-security-and-privacy ***/ user_pref("captivedetect.canonicalURL", ""); user_pref("network.captive-portal-service.enabled", false); // [FF52+] /* 0361: disable Network Connectivity checks [FF65+] * [1] https://bugzilla.mozilla.org/1460537 ***/ user_pref("network.connectivity-service.enabled", false); /*** [SECTION 0400]: SAFE BROWSING (SB) SB has taken many steps to preserve privacy. If required, a full url is never sent to Google, only a part-hash of the prefix, hidden with noise of other real part-hashes. Firefox takes measures such as stripping out identifying parameters and since SBv4 (FF57+) doesn't even use cookies. (#Turn on browser.safebrowsing.debug to monitor this activity) [1] https://feeding.cloud.geek.nz/posts/how-safe-browsing-works-in-firefox/ [2] https://wiki.mozilla.org/Security/Safe_Browsing [3] https://support.mozilla.org/kb/how-does-phishing-and-malware-protection-work [4] https://educatedguesswork.org/posts/safe-browsing-privacy/ ***/ user_pref("_user.js.parrot", "0400 syntax error: the parrot's passed on!"); /* 0401: disable SB (Safe Browsing) * [WARNING] Do this at your own risk! These are the master switches * [SETTING] Privacy & Security>Security>... Block dangerous and deceptive content ***/ user_pref("browser.safebrowsing.malware.enabled", false); user_pref("browser.safebrowsing.phishing.enabled", false); /* 0402: disable SB checks for downloads (both local lookups + remote) * This is the master switch for the safebrowsing.downloads* prefs (0403, 0404) * [SETTING] Privacy & Security>Security>... "Block dangerous downloads" ***/ user_pref("browser.safebrowsing.downloads.enabled", false); /* 0403: disable SB checks for downloads (remote) * To verify the safety of certain executable files, Firefox may submit some information about the * file, including the name, origin, size and a cryptographic hash of the contents, to the Google * Safe Browsing service which helps Firefox determine whether or not the file should be blocked * [SETUP-SECURITY] If you do not understand this, or you want this protection, then override this ***/ user_pref("browser.safebrowsing.downloads.remote.enabled", false); user_pref("browser.safebrowsing.downloads.remote.url", ""); // Defense-in-depth /* 0404: disable SB checks for unwanted software * [SETTING] Privacy & Security>Security>... "Warn you about unwanted and uncommon software" ***/ user_pref("browser.safebrowsing.downloads.remote.block_potentially_unwanted", false); user_pref("browser.safebrowsing.downloads.remote.block_uncommon", false); /* 0405: disable "ignore this warning" on SB warnings [FF45+] * If clicked, it bypasses the block for that session. This is a means for admins to enforce SB * [TEST] see https://github.com/arkenfox/user.js/wiki/Appendix-A-Test-Sites#-mozilla * [1] https://bugzilla.mozilla.org/1226490 ***/ user_pref("browser.safebrowsing.allowOverride", true); /*** [SECTION 0600]: BLOCK IMPLICIT OUTBOUND [not explicitly asked for - e.g. clicked on] ***/ user_pref("_user.js.parrot", "0600 syntax error: the parrot's no more!"); /* 0601: disable link prefetching * [1] https://developer.mozilla.org/docs/Web/HTTP/Link_prefetching_FAQ ***/ user_pref("network.prefetch-next", false); /* 0602: disable DNS prefetching * [1] https://developer.mozilla.org/docs/Web/HTTP/Headers/X-DNS-Prefetch-Control ***/ user_pref("network.dns.disablePrefetch", true); // user_pref("network.dns.disablePrefetchFromHTTPS", true); // [DEFAULT: true] /* 0603: disable predictor / prefetching ***/ user_pref("network.predictor.enabled", false); user_pref("network.predictor.enable-prefetch", false); // [FF48+] [DEFAULT: false] /* 0604: disable link-mouseover opening connection to linked server * [1] https://news.slashdot.org/story/15/08/14/2321202/how-to-quash-firefoxs-silent-requests ***/ user_pref("network.http.speculative-parallel-limit", 0); /* 0605: disable mousedown speculative connections on bookmarks and history [FF98+] ***/ user_pref("browser.places.speculativeConnect.enabled", false); /* 0610: enforce no "Hyperlink Auditing" (click tracking) * [1] https://www.bleepingcomputer.com/news/software/major-browsers-to-prevent-disabling-of-click-tracking-privacy-risk/ ***/ // user_pref("browser.send_pings", false); // [DEFAULT: false] /*** [SECTION 0700]: DNS / DoH / PROXY / SOCKS ***/ user_pref("_user.js.parrot", "0700 syntax error: the parrot's given up the ghost!"); /* 0702: set the proxy server to do any DNS lookups when using SOCKS * e.g. in Tor, this stops your local DNS server from knowing your Tor destination * as a remote Tor node will handle the DNS request * [1] https://trac.torproject.org/projects/tor/wiki/doc/TorifyHOWTO/WebBrowsers ***/ user_pref("network.proxy.socks_remote_dns", true); /* 0703: disable using UNC (Uniform Naming Convention) paths [FF61+] * [SETUP-CHROME] Can break extensions for profiles on network shares * [1] https://bugzilla.mozilla.org/1413868 ***/ user_pref("network.file.disable_unc_paths", true); // [HIDDEN PREF] /* 0704: disable GIO as a potential proxy bypass vector * Gvfs/GIO has a set of supported protocols like obex, network, archive, computer, * dav, cdda, gphoto2, trash, etc. From FF87-117, by default only sftp was accepted * [1] https://bugzilla.mozilla.org/1433507 * [2] https://en.wikipedia.org/wiki/GVfs * [3] https://en.wikipedia.org/wiki/GIO_(software) ***/ user_pref("network.gio.supported-protocols", ""); // [HIDDEN PREF] [DEFAULT: "" FF118+] /* 0705: disable proxy direct failover for system requests [FF91+] * [WARNING] Default true is a security feature against malicious extensions [1] * [SETUP-CHROME] If you use a proxy and you trust your extensions * [1] https://blog.mozilla.org/security/2021/10/25/securing-the-proxy-api-for-firefox-add-ons/ ***/ // user_pref("network.proxy.failover_direct", false); /* 0706: disable proxy bypass for system request failures [FF95+] * RemoteSettings, UpdateService, Telemetry [1] * [WARNING] If false, this will break the fallback for some security features * [SETUP-CHROME] If you use a proxy and you understand the security impact * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=1732792,1733994,1733481 ***/ // user_pref("network.proxy.allow_bypass", false); /* 0710: enable DNS-over-HTTPS (DoH) [FF60+] * 0=default, 2=increased (TRR (Trusted Recursive Resolver) first), 3=max (TRR only), 5=off (no rollout) * see "doh-rollout.home-region": USA 2019, Canada 2021, Russia/Ukraine 2022 [3] * [SETTING] Privacy & Security>DNS over HTTPS * [1] https://hacks.mozilla.org/2018/05/a-cartoon-intro-to-dns-over-https/ * [2] https://wiki.mozilla.org/Security/DOH-resolver-policy * [3] https://support.mozilla.org/en-US/kb/firefox-dns-over-https * [4] https://www.eff.org/deeplinks/2020/12/dns-doh-and-odoh-oh-my-year-review-2020 ***/ user_pref("network.trr.mode", 5); /* 0712: set DoH provider * The custom uri is the value shown when you "Choose provider>Custom>" * [NOTE] If you USE custom then "network.trr.uri" should be set the same * [SETTING] Privacy & Security>DNS over HTTPS>Increased/Max>Choose provider ***/ // user_pref("network.trr.uri", "https://example.dns"); // user_pref("network.trr.custom_uri", "https://example.dns"); /*** [SECTION 0800]: LOCATION BAR / SEARCH BAR / SUGGESTIONS / HISTORY / FORMS ***/ user_pref("_user.js.parrot", "0800 syntax error: the parrot's ceased to be!"); /* 0801: disable location bar making speculative connections [FF56+] * [1] https://bugzilla.mozilla.org/1348275 ***/ user_pref("browser.urlbar.speculativeConnect.enabled", false); /* 0802: disable location bar contextual suggestions * [SETTING] Privacy & Security>Address Bar>Suggestions from... * [1] https://blog.mozilla.org/data/2021/09/15/data-and-firefox-suggest/ ***/ user_pref("browser.urlbar.suggest.quicksuggest.nonsponsored", false); // [FF95+] user_pref("browser.urlbar.suggest.quicksuggest.sponsored", false); // [FF92+] /* 0803: disable live search suggestions * [NOTE] Both must be true for the location bar to work * [SETUP-CHROME] Override these if you trust and use a privacy respecting search engine * [SETTING] Search>Provide search suggestions | Show search suggestions in address bar results ***/ user_pref("browser.search.suggest.enabled", false); user_pref("browser.urlbar.suggest.searches", false); /* 0805: disable urlbar trending search suggestions [FF118+] * [SETTING] Search>Search Suggestions>Show trending search suggestions (FF119) ***/ user_pref("browser.urlbar.trending.featureGate", false); /* 0806: disable urlbar suggestions ***/ user_pref("browser.urlbar.addons.featureGate", false); // [FF115+] user_pref("browser.urlbar.mdn.featureGate", false); // [FF117+] [HIDDEN PREF] user_pref("browser.urlbar.pocket.featureGate", false); // [FF116+] [DEFAULT: false] user_pref("browser.urlbar.weather.featureGate", false); // [FF108+] [DEFAULT: false] /* 0807: disable urlbar clipboard suggestions [FF118+] ***/ // user_pref("browser.urlbar.clipboard.featureGate", false); // [DEFAULT: false] /* 0810: disable search and form history * [SETUP-WEB] Be aware that autocomplete form data can be read by third parties [1][2] * [NOTE] We also clear formdata on exit (2811) * [SETTING] Privacy & Security>History>Custom Settings>Remember search and form history * [1] https://blog.mindedsecurity.com/2011/10/autocompleteagain.html * [2] https://bugzilla.mozilla.org/381681 ***/ user_pref("browser.formfill.enable", false); /* 0815: disable tab-to-search [FF85+] * Alternatively, you can exclude on a per-engine basis by unchecking them in Options>Search * [SETTING] Privacy & Security>Address Bar>When using the address bar, suggest>Search engines ***/ user_pref("browser.urlbar.suggest.engines", false); /* 0820: disable coloring of visited links * [SETUP-HARDEN] Bulk rapid history sniffing was mitigated in 2010 [1][2]. Slower and more expensive * redraw timing attacks were largely mitigated in FF77+ [3]. Using RFP (4501) further hampers timing * attacks. Don't forget clearing history on exit (2811). However, social engineering [2#limits][4][5] * and advanced targeted timing attacks could still produce usable results * [1] https://developer.mozilla.org/docs/Web/CSS/Privacy_and_the_:visited_selector * [2] https://dbaron.org/mozilla/visited-privacy * [3] https://bugzilla.mozilla.org/1632765 * [4] https://earthlng.github.io/testpages/visited_links.html (see github wiki APPENDIX A on how to use) * [5] https://lcamtuf.blogspot.com/2016/08/css-mix-blend-mode-is-bad-for-keeping.html ***/ // user_pref("layout.css.visited_links_enabled", false); /* 0830: enable separate default search engine in Private Windows and its UI setting * [SETTING] Search>Default Search Engine>Choose a different default search engine for Private Windows only ***/ user_pref("browser.search.separatePrivateDefault", true); // [FF70+] user_pref("browser.search.separatePrivateDefault.ui.enabled", true); // [FF71+] /*** [SECTION 0900]: PASSWORDS [1] https://support.mozilla.org/kb/use-primary-password-protect-stored-logins-and-pas ***/ user_pref("_user.js.parrot", "0900 syntax error: the parrot's expired!"); /* 0903: disable auto-filling username & password form fields * can leak in cross-site forms *and* be spoofed * [NOTE] Username & password is still available when you enter the field * [SETTING] Privacy & Security>Logins and Passwords>Autofill logins and passwords * [1] https://freedom-to-tinker.com/2017/12/27/no-boundaries-for-user-identities-web-trackers-exploit-browser-login-managers/ * [2] https://homes.esat.kuleuven.be/~asenol/leaky-forms/ ***/ user_pref("signon.autofillForms", false); /* 0904: disable formless login capture for Password Manager [FF51+] ***/ user_pref("signon.formlessCapture.enabled", false); /* 0905: limit (or disable) HTTP authentication credentials dialogs triggered by sub-resources [FF41+] * hardens against potential credentials phishing * 0 = don't allow sub-resources to open HTTP authentication credentials dialogs * 1 = don't allow cross-origin sub-resources to open HTTP authentication credentials dialogs * 2 = allow sub-resources to open HTTP authentication credentials dialogs (default) ***/ user_pref("network.auth.subresource-http-auth-allow", 1); /* 0906: enforce no automatic authentication on Microsoft sites [FF91+] [WINDOWS 10+] * [SETTING] Privacy & Security>Logins and Passwords>Allow Windows single sign-on for... * [1] https://support.mozilla.org/kb/windows-sso ***/ // user_pref("network.http.windows-sso.enabled", false); // [DEFAULT: false] /*** [SECTION 1000]: DISK AVOIDANCE ***/ user_pref("_user.js.parrot", "1000 syntax error: the parrot's gone to meet 'is maker!"); /* 1005: disable automatic Firefox start and session restore after reboot [FF62+] [WINDOWS] * [1] https://bugzilla.mozilla.org/603903 ***/ user_pref("toolkit.winRegisterApplicationRestart", false); /* 1006: disable favicons in shortcuts [WINDOWS] * URL shortcuts use a cached randomly named .ico file which is stored in your * profile/shortcutCache directory. The .ico remains after the shortcut is deleted * If set to false then the shortcuts use a generic Firefox icon ***/ user_pref("browser.shell.shortcutFavicons", false); /*** [SECTION 1200]: HTTPS (SSL/TLS / OCSP / CERTS / HPKP) Your cipher and other settings can be used in server side fingerprinting [TEST] https://www.ssllabs.com/ssltest/viewMyClient.html [TEST] https://browserleaks.com/ssl [TEST] https://ja3er.com/ [1] https://www.securityartwork.es/2017/02/02/tls-client-fingerprinting-with-bro/ ***/ user_pref("_user.js.parrot", "1200 syntax error: the parrot's a stiff!"); /** SSL (Secure Sockets Layer) / TLS (Transport Layer Security) ***/ /* 1201: require safe negotiation * Blocks connections to servers that don't support RFC 5746 [2] as they're potentially vulnerable to a * MiTM attack [3]. A server without RFC 5746 can be safe from the attack if it disables renegotiations * but the problem is that the browser can't know that. Setting this pref to true is the only way for the * browser to ensure there will be no unsafe renegotiations on the channel between the browser and the server * [SETUP-WEB] SSL_ERROR_UNSAFE_NEGOTIATION: is it worth overriding this for that one site? * [STATS] SSL Labs (Nov 2023) reports over 99.5% of top sites have secure renegotiation [4] * [1] https://wiki.mozilla.org/Security:Renegotiation * [2] https://datatracker.ietf.org/doc/html/rfc5746 * [3] https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-3555 * [4] https://www.ssllabs.com/ssl-pulse/ ***/ user_pref("security.ssl.require_safe_negotiation", true); /* 1206: disable TLS1.3 0-RTT (round-trip time) [FF51+] * This data is not forward secret, as it is encrypted solely under keys derived using * the offered PSK. There are no guarantees of non-replay between connections * [1] https://github.com/tlswg/tls13-spec/issues/1001 * [2] https://www.rfc-editor.org/rfc/rfc9001.html#name-replay-attacks-with-0-rtt * [3] https://blog.cloudflare.com/tls-1-3-overview-and-q-and-a/ ***/ user_pref("security.tls.enable_0rtt_data", false); /** OCSP (Online Certificate Status Protocol) [1] https://scotthelme.co.uk/revocation-is-broken/ [2] https://blog.mozilla.org/security/2013/07/29/ocsp-stapling-in-firefox/ ***/ /* 1211: enforce OCSP fetching to confirm current validity of certificates * 0=disabled, 1=enabled (default), 2=enabled for EV certificates only * OCSP (non-stapled) leaks information about the sites you visit to the CA (cert authority) * It's a trade-off between security (checking) and privacy (leaking info to the CA) * [NOTE] This pref only controls OCSP fetching and does not affect OCSP stapling * [SETTING] Privacy & Security>Security>Certificates>Query OCSP responder servers... * [1] https://en.wikipedia.org/wiki/Ocsp ***/ user_pref("security.OCSP.enabled", 1); // [DEFAULT: 1] /* 1212: set OCSP fetch failures (non-stapled, see 1211) to hard-fail * [SETUP-WEB] SEC_ERROR_OCSP_SERVER_ERROR * When a CA cannot be reached to validate a cert, Firefox just continues the connection (=soft-fail) * Setting this pref to true tells Firefox to instead terminate the connection (=hard-fail) * It is pointless to soft-fail when an OCSP fetch fails: you cannot confirm a cert is still valid (it * could have been revoked) and/or you could be under attack (e.g. malicious blocking of OCSP servers) * [1] https://blog.mozilla.org/security/2013/07/29/ocsp-stapling-in-firefox/ * [2] https://www.imperialviolet.org/2014/04/19/revchecking.html ***/ user_pref("security.OCSP.require", true); /** CERTS / HPKP (HTTP Public Key Pinning) ***/ /* 1223: enable strict PKP (Public Key Pinning) * 0=disabled, 1=allow user MiTM (default; such as your antivirus), 2=strict * [SETUP-WEB] MOZILLA_PKIX_ERROR_KEY_PINNING_FAILURE ***/ user_pref("security.cert_pinning.enforcement_level", 2); /* 1224: enable CRLite [FF73+] * 0 = disabled * 1 = consult CRLite but only collect telemetry * 2 = consult CRLite and enforce both "Revoked" and "Not Revoked" results * 3 = consult CRLite and enforce "Not Revoked" results, but defer to OCSP for "Revoked" (default) * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=1429800,1670985,1753071 * [2] https://blog.mozilla.org/security/tag/crlite/ ***/ user_pref("security.remote_settings.crlite_filters.enabled", true); user_pref("security.pki.crlite_mode", 2); /** MIXED CONTENT ***/ /* 1241: disable insecure passive content (such as images) on https pages ***/ // user_pref("security.mixed_content.block_display_content", true); // Defense-in-depth (see 1244) /* 1244: enable HTTPS-Only mode in all windows * When the top-level is HTTPS, insecure subresources are also upgraded (silent fail) * [SETTING] to add site exceptions: Padlock>HTTPS-Only mode>On (after "Continue to HTTP Site") * [SETTING] Privacy & Security>HTTPS-Only Mode (and manage exceptions) * [TEST] http://example.com [upgrade] * [TEST] http://httpforever.com/ | http://http.rip [no upgrade] ***/ user_pref("dom.security.https_only_mode", true); // [FF76+] // user_pref("dom.security.https_only_mode_pbm", true); // [FF80+] /* 1245: enable HTTPS-Only mode for local resources [FF77+] ***/ // user_pref("dom.security.https_only_mode.upgrade_local", true); /* 1246: disable HTTP background requests [FF82+] * When attempting to upgrade, if the server doesn't respond within 3 seconds, Firefox sends * a top-level HTTP request without path in order to check if the server supports HTTPS or not * This is done to avoid waiting for a timeout which takes 90 seconds * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=1642387,1660945 ***/ user_pref("dom.security.https_only_mode_send_http_background_request", false); /** UI (User Interface) ***/ /* 1270: display warning on the padlock for "broken security" (if 1201 is false) * Bug: warning padlock not indicated for subresources on a secure page! [2] * [1] https://wiki.mozilla.org/Security:Renegotiation * [2] https://bugzilla.mozilla.org/1353705 ***/ user_pref("security.ssl.treat_unsafe_negotiation_as_broken", true); /* 1272: display advanced information on Insecure Connection warning pages * only works when it's possible to add an exception * i.e. it doesn't work for HSTS discrepancies (https://subdomain.preloaded-hsts.badssl.com/) * [TEST] https://expired.badssl.com/ ***/ user_pref("browser.xul.error_pages.expert_bad_cert", true); /*** [SECTION 1700]: CONTAINERS ***/ user_pref("_user.js.parrot", "1700 syntax error: the parrot's bit the dust!"); /* 1701: enable Container Tabs and its UI setting [FF50+] * [SETTING] General>Tabs>Enable Container Tabs * https://wiki.mozilla.org/Security/Contextual_Identity_Project/Containers ***/ user_pref("privacy.userContext.enabled", true); user_pref("privacy.userContext.ui.enabled", true); /* 1702: set behavior on "+ Tab" button to display container menu on left click [FF74+] * [NOTE] The menu is always shown on long press and right click * [SETTING] General>Tabs>Enable Container Tabs>Settings>Select a container for each new tab ***/ // user_pref("privacy.userContext.newTabContainerOnLeftClick.enabled", true); /*** [SECTION 2000]: PLUGINS / MEDIA / WEBRTC ***/ user_pref("_user.js.parrot", "2000 syntax error: the parrot's snuffed it!"); /* 2004: force exclusion of private IPs from ICE candidates [FF51+] * [SETUP-HARDEN] This will protect your private IP even in TRUSTED scenarios after you * grant device access, but often results in breakage on video-conferencing platforms ***/ // user_pref("media.peerconnection.ice.no_host", true); /* 2020: disable GMP (Gecko Media Plugins) * [1] https://wiki.mozilla.org/GeckoMediaPlugins ***/ // user_pref("media.gmp-provider.enabled", false); /*** [SECTION 2400]: DOM (DOCUMENT OBJECT MODEL) ***/ user_pref("_user.js.parrot", "2400 syntax error: the parrot's kicked the bucket!"); /* 2402: prevent scripts from moving and resizing open windows ***/ user_pref("dom.disable_window_move_resize", true); /*** [SECTION 2600]: MISCELLANEOUS ***/ user_pref("_user.js.parrot", "2600 syntax error: the parrot's run down the curtain!"); /* 2603: remove temp files opened from non-PB windows with an external application * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=302433,1738574 ***/ user_pref("browser.download.start_downloads_in_tmp_dir", true); // [FF102+] user_pref("browser.helperApps.deleteTempFileOnExit", true); /* 2606: disable UITour backend so there is no chance that a remote page can use it ***/ user_pref("browser.uitour.enabled", false); // user_pref("browser.uitour.url", ""); // Defense-in-depth /* 2608: reset remote debugging to disabled * [1] https://gitlab.torproject.org/tpo/applications/tor-browser/-/issues/16222 ***/ user_pref("devtools.debugger.remote-enabled", false); // [DEFAULT: false] /* 2615: disable websites overriding Firefox's keyboard shortcuts [FF58+] * 0 (default) or 1=allow, 2=block * [SETTING] to add site exceptions: Ctrl+I>Permissions>Override Keyboard Shortcuts ***/ // user_pref("permissions.default.shortcuts", 2); /* 2616: remove special permissions for certain mozilla domains [FF35+] * [1] resource://app/defaults/permissions ***/ user_pref("permissions.manager.defaultsUrl", ""); /* 2617: remove webchannel whitelist ***/ user_pref("webchannel.allowObject.urlWhitelist", ""); /* 2619: use Punycode in Internationalized Domain Names to eliminate possible spoofing * [SETUP-WEB] Might be undesirable for non-latin alphabet users since legitimate IDN's are also punycoded * [TEST] https://www.xn--80ak6aa92e.com/ (www.apple.com) * [1] https://wiki.mozilla.org/IDN_Display_Algorithm * [2] https://en.wikipedia.org/wiki/IDN_homograph_attack * [3] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=punycode+firefox * [4] https://www.xudongz.com/blog/2017/idn-phishing/ ***/ user_pref("network.IDN_show_punycode", true); /* 2620: enforce PDFJS, disable PDFJS scripting * This setting controls if the option "Display in Firefox" is available in the setting below * and by effect controls whether PDFs are handled in-browser or externally ("Ask" or "Open With") * [WHY] pdfjs is lightweight, open source, and secure: the last exploit was June 2015 [1] * It doesn't break "state separation" of browser content (by not sharing with OS, independent apps). * It maintains disk avoidance and application data isolation. It's convenient. You can still save to disk. * [NOTE] JS can still force a pdf to open in-browser by bundling its own code * [SETUP-CHROME] You may prefer a different pdf reader for security/workflow reasons * [SETTING] General>Applications>Portable Document Format (PDF) * [1] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=pdf.js+firefox ***/ user_pref("pdfjs.disabled", false); // [DEFAULT: false] user_pref("pdfjs.enableScripting", false); // [FF86+] /* 2624: disable middle click on new tab button opening URLs or searches using clipboard [FF115+] */ user_pref("browser.tabs.searchclipboardfor.middleclick", false); // [DEFAULT: false NON-LINUX] /** DOWNLOADS ***/ /* 2652: disable downloads panel opening on every download [FF96+] ***/ user_pref("browser.download.alwaysOpenPanel", false); /* 2653: disable adding downloads to the system's "recent documents" list ***/ user_pref("browser.download.manager.addToRecentDocs", false); /* 2654: enable user interaction for security by always asking how to handle new mimetypes [FF101+] * [SETTING] General>Files and Applications>What should Firefox do with other files ***/ user_pref("browser.download.always_ask_before_handling_new_types", true); /** EXTENSIONS ***/ /* 2661: disable bypassing 3rd party extension install prompts [FF82+] * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=1659530,1681331 ***/ user_pref("extensions.postDownloadThirdPartyPrompt", false); /* 2662: disable webextension restrictions on certain mozilla domains (you also need 4503) [FF60+] * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=1384330,1406795,1415644,1453988 ***/ // user_pref("extensions.webextensions.restrictedDomains", ""); /*** [SECTION 2700]: ETP (ENHANCED TRACKING PROTECTION) ***/ user_pref("_user.js.parrot", "2700 syntax error: the parrot's joined the bleedin' choir invisible!"); /* 2701: enable ETP Strict Mode [FF86+] * ETP Strict Mode enables Total Cookie Protection (TCP) * [NOTE] Adding site exceptions disables all ETP protections for that site and increases the risk of * cross-site state tracking e.g. exceptions for SiteA and SiteB means PartyC on both sites is shared * [1] https://blog.mozilla.org/security/2021/02/23/total-cookie-protection/ * [SETTING] to add site exceptions: Urlbar>ETP Shield * [SETTING] to manage site exceptions: Options>Privacy & Security>Enhanced Tracking Protection>Manage Exceptions ***/ user_pref("browser.contentblocking.category", "strict"); // [HIDDEN PREF] /* 2702: disable ETP web compat features [FF93+] * [SETUP-HARDEN] Includes skip lists, heuristics (SmartBlock) and automatic grants * Opener and redirect heuristics are granted for 30 days, see [3] * [1] https://blog.mozilla.org/security/2021/07/13/smartblock-v2/ * [2] https://hg.mozilla.org/mozilla-central/rev/e5483fd469ab#l4.12 * [3] https://developer.mozilla.org/en-US/docs/Web/Privacy/State_Partitioning#storage_access_heuristics ***/ // user_pref("privacy.antitracking.enableWebcompat", false); /*** [SECTION 2800]: SHUTDOWN & SANITIZING ***/ user_pref("_user.js.parrot", "2800 syntax error: the parrot's bleedin' demised!"); /** SANITIZE MANUAL: IGNORES "ALLOW" SITE EXCEPTIONS ***/ /* 2820: reset default items to clear with Ctrl-Shift-Del [SETUP-CHROME] * This dialog can also be accessed from the menu History>Clear Recent History * Firefox remembers your last choices. This will reset them when you start Firefox * [NOTE] Regardless of what you set "downloads" to, as soon as the dialog * for "Clear Recent History" is opened, it is synced to the same as "history" ***/ user_pref("privacy.cpd.cache", true); // [DEFAULT: true] user_pref("privacy.cpd.formdata", true); // [DEFAULT: true] user_pref("privacy.cpd.history", true); // [DEFAULT: true] user_pref("privacy.cpd.sessions", true); // [DEFAULT: true] user_pref("privacy.cpd.offlineApps", false); // [DEFAULT: false] user_pref("privacy.cpd.cookies", true); // user_pref("privacy.cpd.downloads", true); // not used, see note above // user_pref("privacy.cpd.openWindows", false); // Session Restore // user_pref("privacy.cpd.passwords", false); user_pref("privacy.cpd.siteSettings", true); /* 2822: reset default "Time range to clear" for "Clear Recent History" (2820) * Firefox remembers your last choice. This will reset the value when you start Firefox * 0=everything, 1=last hour, 2=last two hours, 3=last four hours, 4=today * [NOTE] Values 5 (last 5 minutes) and 6 (last 24 hours) are not listed in the dropdown, * which will display a blank value, and are not guaranteed to work ***/ user_pref("privacy.sanitize.timeSpan", 1); /*** [SECTION 4000]: FPP (fingerprintingProtection) RFP (4501) overrides FPP In FF118+ FPP is on by default in private windows (4001) and in FF119+ is controlled by ETP (2701). FPP will also use Remote Services in future to relax FPP protections on a per site basis for compatibility (pref coming). 1826408 - restrict fonts to system (kBaseFonts + kLangPackFonts) (Windows, Mac, some Linux) https://searchfox.org/mozilla-central/search?path=StandardFonts*.inc 1858181 - subtly randomize canvas per eTLD+1, per session and per window-mode (FF120+) ***/ user_pref("_user.js.parrot", "1400 syntax error: the parrot's bereft of life!"); /* 4001: enable FPP in PB mode [FF114+] * [NOTE] In FF119+, FPP for all modes (7106) is enabled with ETP Strict (2701) ***/ // user_pref("privacy.fingerprintingProtection.pbmode", true); // [DEFAULT: true FF118+] /* 4002: set global FPP overrides [FF114+] * Controls what protections FPP uses globally, including "RFPTargets" (despite the name these are * not used by RFP) e.g. "+AllTargets,-CSSPrefersColorScheme" or "-AllTargets,+CanvasRandomization" * [NOTE] Be aware that not all RFP protections are necessarily in RFPTargets * [WARNING] Not recommended. Either use RFP or FPP at defaults * [1] https://searchfox.org/mozilla-central/source/toolkit/components/resistfingerprinting/RFPTargets.inc ***/ // user_pref("privacy.fingerprintingProtection.overrides", ""); /*** [SECTION 5000]: OPTIONAL OPSEC Disk avoidance, application data isolation, eyeballs... ***/ user_pref("_user.js.parrot", "5000 syntax error: the parrot's taken 'is last bow"); /* 5001: start Firefox in PB (Private Browsing) mode * [NOTE] In this mode all windows are "private windows" and the PB mode icon is not displayed * [NOTE] The P in PB mode can be misleading: it means no "persistent" disk state such as history, * caches, searches, cookies, localStorage, IndexedDB etc (which you can achieve in normal mode). * In fact, PB mode limits or removes the ability to control some of these, and you need to quit * Firefox to clear them. PB is best used as a one off window (Menu>New Private Window) to provide * a temporary self-contained new session. Close all private windows to clear the PB session. * [SETTING] Privacy & Security>History>Custom Settings>Always use private browsing mode * [1] https://wiki.mozilla.org/Private_Browsing * [2] https://support.mozilla.org/kb/common-myths-about-private-browsing ***/ // user_pref("browser.privatebrowsing.autostart", true); /* 5002: disable memory cache * capacity: -1=determine dynamically (default), 0=none, n=memory capacity in kibibytes ***/ // user_pref("browser.cache.memory.enable", false); // user_pref("browser.cache.memory.capacity", 0); /* 5003: disable saving passwords * [NOTE] This does not clear any passwords already saved * [SETTING] Privacy & Security>Logins and Passwords>Ask to save logins and passwords for websites ***/ // user_pref("signon.rememberSignons", false); /* 5004: disable permissions manager from writing to disk [FF41+] [RESTART] * [NOTE] This means any permission changes are session only * [1] https://bugzilla.mozilla.org/967812 ***/ // user_pref("permissions.memory_only", true); // [HIDDEN PREF] /* 5005: disable intermediate certificate caching [FF41+] [RESTART] * [NOTE] This affects login/cert/key dbs. The effect is all credentials are session-only. * Saved logins and passwords are not available. Reset the pref and restart to return them ***/ // user_pref("security.nocertdb", true); /* 5006: disable favicons in history and bookmarks * [NOTE] Stored as data blobs in favicons.sqlite, these don't reveal anything that your * actual history (and bookmarks) already do. Your history is more detailed, so * control that instead; e.g. disable history, clear history on exit, use PB mode * [NOTE] favicons.sqlite is sanitized on Firefox close ***/ // user_pref("browser.chrome.site_icons", false); /* 5007: exclude "Undo Closed Tabs" in Session Restore ***/ // user_pref("browser.sessionstore.max_tabs_undo", 0); /* 5008: disable resuming session from crash * [TEST] about:crashparent ***/ // user_pref("browser.sessionstore.resume_from_crash", false); /* 5009: disable "open with" in download dialog [FF50+] * Application data isolation [1] * [1] https://bugzilla.mozilla.org/1281959 ***/ // user_pref("browser.download.forbid_open_with", true); /* 5010: disable location bar suggestion types * [SETTING] Privacy & Security>Address Bar>When using the address bar, suggest ***/ // user_pref("browser.urlbar.suggest.history", false); // user_pref("browser.urlbar.suggest.bookmark", false); // user_pref("browser.urlbar.suggest.openpage", false); // user_pref("browser.urlbar.suggest.topsites", false); // [FF78+] /* 5011: disable location bar dropdown * This value controls the total number of entries to appear in the location bar dropdown ***/ // user_pref("browser.urlbar.maxRichResults", 0); /* 5012: disable location bar autofill * [1] https://support.mozilla.org/kb/address-bar-autocomplete-firefox#w_url-autocomplete ***/ // user_pref("browser.urlbar.autoFill", false); /* 5013: disable browsing and download history * [NOTE] We also clear history and downloads on exit (2811) * [SETTING] Privacy & Security>History>Custom Settings>Remember browsing and download history ***/ // user_pref("places.history.enabled", false); /* 5014: disable Windows jumplist [WINDOWS] ***/ // user_pref("browser.taskbar.lists.enabled", false); // user_pref("browser.taskbar.lists.frequent.enabled", false); // user_pref("browser.taskbar.lists.recent.enabled", false); // user_pref("browser.taskbar.lists.tasks.enabled", false); /* 5016: discourage downloading to desktop * 0=desktop, 1=downloads (default), 2=custom * [SETTING] To set your custom default "downloads": General>Downloads>Save files to ***/ // user_pref("browser.download.folderList", 2); /* 5017: disable Form Autofill * If .supportedCountries includes your region (browser.search.region) and .supported * is "detect" (default), then the UI will show. Stored data is not secure, uses JSON * [SETTING] Privacy & Security>Forms and Autofill>Autofill addresses * [1] https://wiki.mozilla.org/Firefox/Features/Form_Autofill ***/ // user_pref("extensions.formautofill.addresses.enabled", false); // [FF55+] // user_pref("extensions.formautofill.creditCards.enabled", false); // [FF56+] /* 5018: limit events that can cause a pop-up ***/ user_pref("dom.popup_allowed_events", "click dblclick mousedown pointerdown"); /* 5019: disable page thumbnail collection ***/ user_pref("browser.pagethumbnails.capturing_disabled", true); // [HIDDEN PREF] /* 5020: disable Windows native notifications and use app notications instead [FF111+] [WINDOWS] ***/ // user_pref("alerts.useSystemBackend.windows.notificationserver.enabled", false); /* 5021: disable location bar using search * Don't leak URL typos to a search engine, give an error message instead * Examples: "secretplace,com", "secretplace/com", "secretplace com", "secret place.com" * [NOTE] This does not affect explicit user action such as using search buttons in the * dropdown, or using keyword search shortcuts you configure in options (e.g. "d" for DuckDuckGo) ***/ user_pref("keyword.enabled", false); /*** [SECTION 5500]: OPTIONAL HARDENING Not recommended. Overriding these can cause breakage and performance issues, they are mostly fingerprintable, and the threat model is practically nonexistent ***/ user_pref("_user.js.parrot", "5500 syntax error: this is an ex-parrot!"); /* 5501: disable MathML (Mathematical Markup Language) [FF51+] * [1] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=mathml ***/ // user_pref("mathml.disabled", true); // 1173199 /* 5502: disable in-content SVG (Scalable Vector Graphics) [FF53+] * [1] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=firefox+svg ***/ // user_pref("svg.disabled", true); // 1216893 /* 5503: disable graphite * [1] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=firefox+graphite * [2] https://en.wikipedia.org/wiki/Graphite_(SIL) ***/ // user_pref("gfx.font_rendering.graphite.enabled", false); /* 5504: disable asm.js [FF22+] * [1] http://asmjs.org/ * [2] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=asm.js * [3] https://rh0dev.github.io/blog/2017/the-return-of-the-jit/ ***/ // user_pref("javascript.options.asmjs", false); /* 5505: disable Ion and baseline JIT to harden against JS exploits * [NOTE] When both Ion and JIT are disabled, and trustedprincipals * is enabled, then Ion can still be used by extensions (1599226) * [1] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=firefox+jit * [2] https://microsoftedge.github.io/edgevr/posts/Super-Duper-Secure-Mode/ ***/ // user_pref("javascript.options.ion", false); // user_pref("javascript.options.baselinejit", false); // user_pref("javascript.options.jit_trustedprincipals", true); // [FF75+] [HIDDEN PREF] /* 5506: disable WebAssembly [FF52+] * Vulnerabilities [1] have increasingly been found, including those known and fixed * in native programs years ago [2]. WASM has powerful low-level access, making * certain attacks (brute-force) and vulnerabilities more possible * [STATS] ~0.2% of websites, about half of which are for cryptomining / malvertising [2][3] * [1] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=wasm * [2] https://spectrum.ieee.org/tech-talk/telecom/security/more-worries-over-the-security-of-web-assembly * [3] https://www.zdnet.com/article/half-of-the-websites-using-webassembly-use-it-for-malicious-purposes ***/ // user_pref("javascript.options.wasm", false); /* 5507: disable rendering of SVG OpenType fonts ***/ // user_pref("gfx.font_rendering.opentype_svg.enabled", false); /* 5508: disable all DRM content (EME: Encryption Media Extension) * Optionally hide the UI setting which also disables the DRM prompt * [SETTING] General>DRM Content>Play DRM-controlled content * [TEST] https://bitmovin.com/demos/drm * [1] https://www.eff.org/deeplinks/2017/10/drms-dead-canary-how-we-just-lost-web-what-we-learned-it-and-what-we-need-do-next ***/ // user_pref("media.eme.enabled", false); // user_pref("browser.eme.ui.enabled", false); /* 5509: disable IPv6 if using a VPN * This is an application level fallback. Disabling IPv6 is best done at an OS/network * level, and/or configured properly in system wide VPN setups. * [SETUP-WEB] PR_CONNECT_RESET_ERROR * [NOTE] PHP defaults to IPv6 with "localhost". Use "php -S 127.0.0.1:PORT" * [TEST] https://ipleak.org/ * [1] https://www.internetsociety.org/tag/ipv6-security/ (Myths 2,4,5,6) ***/ // user_pref("network.dns.disableIPv6", true); /* 5510: control when to send a cross-origin referer * 0=always (default), 1=only if base domains match, 2=only if hosts match * [NOTE] Will cause breakage: older modems/routers and some sites e.g banks, vimeo, icloud, instagram ***/ // user_pref("network.http.referer.XOriginPolicy", 2); /* 5511: set DoH bootstrap address [FF89+] * Firefox uses the system DNS to initially resolve the IP address of your DoH server. * When set to a valid, working value that matches your "network.trr.uri" (0712) Firefox * won't use the system DNS. If the IP doesn't match then DoH won't work ***/ // user_pref("network.trr.bootstrapAddr", "10.0.0.1"); // [HIDDEN PREF] /*** [SECTION 6000]: DON'T TOUCH ***/ user_pref("_user.js.parrot", "6000 syntax error: the parrot's 'istory!"); /* 6001: enforce Firefox blocklist * [WHY] It includes updates for "revoked certificates" * [1] https://blog.mozilla.org/security/2015/03/03/revoking-intermediate-certificates-introducing-onecrl/ ***/ user_pref("extensions.blocklist.enabled", true); // [DEFAULT: true] /* 6002: enforce no referer spoofing * [WHY] Spoofing can affect CSRF (Cross-Site Request Forgery) protections ***/ user_pref("network.http.referer.spoofSource", false); // [DEFAULT: false] /* 6004: enforce a security delay on some confirmation dialogs such as install, open/save * [1] https://www.squarefree.com/2004/07/01/race-conditions-in-security-dialogs/ ***/ user_pref("security.dialog_enable_delay", 1000); // [DEFAULT: 1000] /* 6008: enforce no First Party Isolation [FF51+] * [WARNING] Replaced with network partitioning (FF85+) and TCP (2701), and enabling FPI * disables those. FPI is no longer maintained except at Tor Project for Tor Browser's config ***/ user_pref("privacy.firstparty.isolate", false); // [DEFAULT: false] /* 6009: enforce SmartBlock shims (about:compat) [FF81+] * [1] https://blog.mozilla.org/security/2021/03/23/introducing-smartblock/ ***/ user_pref("extensions.webcompat.enable_shims", true); // [HIDDEN PREF] [DEFAULT: true] /* 6010: enforce no TLS 1.0/1.1 downgrades * [TEST] https://tls-v1-1.badssl.com:1010/ ***/ user_pref("security.tls.version.enable-deprecated", false); // [DEFAULT: false] /* 6011: enforce disabling of Web Compatibility Reporter [FF56+] * Web Compatibility Reporter adds a "Report Site Issue" button to send data to Mozilla * [WHY] To prevent wasting Mozilla's time with a custom setup ***/ user_pref("extensions.webcompat-reporter.enabled", false); // [DEFAULT: false] /* 6012: enforce Quarantined Domains [FF115+] * [WHY] https://support.mozilla.org/kb/quarantined-domains */ user_pref("extensions.quarantinedDomains.enabled", true); // [DEFAULT: true] /* 6050: prefsCleaner: previously active items removed from arkenfox 115-127 ***/ // user_pref("accessibility.force_disabled", ""); // user_pref("browser.urlbar.dnsResolveSingleWordsAfterSearch", ""); // user_pref("network.protocol-handler.external.ms-windows-store", ""); // user_pref("privacy.partition.always_partition_third_party_non_cookie_storage", ""); // user_pref("privacy.partition.always_partition_third_party_non_cookie_storage.exempt_sessionstorage", ""); // user_pref("privacy.partition.serviceWorkers", ""); /*** [SECTION 7000]: DON'T BOTHER ***/ user_pref("_user.js.parrot", "7000 syntax error: the parrot's pushing up daisies!"); /* 7001: disable APIs * Location-Aware Browsing, Full Screen * [WHY] The API state is easily fingerprintable. * Geo is behind a prompt (7002). Full screen requires user interaction ***/ // user_pref("geo.enabled", false); // user_pref("full-screen-api.enabled", false); /* 7002: set default permissions * Location, Camera, Microphone, Notifications [FF58+] Virtual Reality [FF73+] * 0=always ask (default), 1=allow, 2=block * [WHY] These are fingerprintable via Permissions API, except VR. Just add site * exceptions as allow/block for frequently visited/annoying sites: i.e. not global * [SETTING] to add site exceptions: Ctrl+I>Permissions> * [SETTING] to manage site exceptions: Options>Privacy & Security>Permissions>Settings ***/ // user_pref("permissions.default.geo", 0); // user_pref("permissions.default.camera", 0); // user_pref("permissions.default.microphone", 0); // user_pref("permissions.default.desktop-notification", 0); // user_pref("permissions.default.xr", 0); // Virtual Reality /* 7003: disable non-modern cipher suites [1] * [WHY] Passive fingerprinting. Minimal/non-existent threat of downgrade attacks * [1] https://browserleaks.com/ssl ***/ // user_pref("security.ssl3.ecdhe_ecdsa_aes_128_sha", false); // user_pref("security.ssl3.ecdhe_ecdsa_aes_256_sha", false); // user_pref("security.ssl3.ecdhe_rsa_aes_128_sha", false); // user_pref("security.ssl3.ecdhe_rsa_aes_256_sha", false); // user_pref("security.ssl3.rsa_aes_128_gcm_sha256", false); // no PFS // user_pref("security.ssl3.rsa_aes_256_gcm_sha384", false); // no PFS // user_pref("security.ssl3.rsa_aes_128_sha", false); // no PFS // user_pref("security.ssl3.rsa_aes_256_sha", false); // no PFS /* 7004: control TLS versions * [WHY] Passive fingerprinting and security ***/ // user_pref("security.tls.version.min", 3); // [DEFAULT: 3] // user_pref("security.tls.version.max", 4); /* 7005: disable SSL session IDs [FF36+] * [WHY] Passive fingerprinting and perf costs. These are session-only * and isolated with network partitioning (FF85+) and/or containers ***/ // user_pref("security.ssl.disable_session_identifiers", true); /* 7006: onions * [WHY] Firefox doesn't support hidden services. Use Tor Browser ***/ // user_pref("dom.securecontext.allowlist_onions", true); // [FF97+] 1382359/1744006 // user_pref("network.http.referer.hideOnionSource", true); // 1305144 /* 7007: referers * [WHY] Only cross-origin referers (1602, 5510) matter ***/ // user_pref("network.http.sendRefererHeader", 2); // user_pref("network.http.referer.trimmingPolicy", 0); /* 7008: set the default Referrer Policy [FF59+] * 0=no-referer, 1=same-origin, 2=strict-origin-when-cross-origin, 3=no-referrer-when-downgrade * [WHY] Defaults are fine. They can be overridden by a site-controlled Referrer Policy ***/ // user_pref("network.http.referer.defaultPolicy", 2); // [DEFAULT: 2] // user_pref("network.http.referer.defaultPolicy.pbmode", 2); // [DEFAULT: 2] /* 7010: disable HTTP Alternative Services [FF37+] * [WHY] Already isolated with network partitioning (FF85+) ***/ // user_pref("network.http.altsvc.enabled", false); /* 7011: disable website control over browser right-click context menu * [WHY] Just use Shift-Right-Click ***/ // user_pref("dom.event.contextmenu.enabled", false); /* 7012: disable icon fonts (glyphs) and local fallback rendering * [WHY] Breakage, font fallback is equivalency, also RFP * [1] https://bugzilla.mozilla.org/789788 * [2] https://gitlab.torproject.org/legacy/trac/-/issues/8455 ***/ // user_pref("gfx.downloadable_fonts.enabled", false); // [FF41+] // user_pref("gfx.downloadable_fonts.fallback_delay", -1); /* 7013: disable Clipboard API * [WHY] Fingerprintable. Breakage. Cut/copy/paste require user * interaction, and paste is limited to focused editable fields ***/ // user_pref("dom.event.clipboardevents.enabled", false); /* 7014: disable System Add-on updates * [WHY] It can compromise security. System addons ship with prefs, use those ***/ // user_pref("extensions.systemAddon.update.enabled", false); // [FF62+] // user_pref("extensions.systemAddon.update.url", ""); // [FF44+] /* 7015: enable the DNT (Do Not Track) HTTP header * [WHY] DNT is enforced with Tracking Protection which is used in ETP Strict (2701) ***/ // user_pref("privacy.donottrackheader.enabled", true); /* 7016: customize ETP settings * [NOTE] FPP (fingerprintingProtection) is ignored when RFP (4501) is enabled * [WHY] Arkenfox only supports strict (2701) which sets these at runtime ***/ // user_pref("network.cookie.cookieBehavior", 5); // [DEFAULT: 5] // user_pref("privacy.fingerprintingProtection", true); // [FF114+] [ETP FF119+] // user_pref("network.http.referer.disallowCrossSiteRelaxingDefault", true); // user_pref("network.http.referer.disallowCrossSiteRelaxingDefault.top_navigation", true); // [FF100+] // user_pref("privacy.partition.network_state.ocsp_cache", true); // [DEFAULT: true FF123+] // user_pref("privacy.query_stripping.enabled", true); // [FF101+] // user_pref("privacy.trackingprotection.enabled", true); // user_pref("privacy.trackingprotection.socialtracking.enabled", true); // user_pref("privacy.trackingprotection.cryptomining.enabled", true); // [DEFAULT: true] // user_pref("privacy.trackingprotection.fingerprinting.enabled", true); // [DEFAULT: true] /* 7017: disable service workers * [WHY] Already isolated with TCP (2701) behind a pref (2710) ***/ // user_pref("dom.serviceWorkers.enabled", false); /* 7018: disable Web Notifications [FF22+] * [WHY] Web Notifications are behind a prompt (7002) * [1] https://blog.mozilla.org/en/products/firefox/block-notification-requests/ ***/ // user_pref("dom.webnotifications.enabled", false); /* 7019: disable Push Notifications [FF44+] * [WHY] Push requires subscription * [NOTE] To remove all subscriptions, reset "dom.push.userAgentID" * [1] https://support.mozilla.org/kb/push-notifications-firefox ***/ // user_pref("dom.push.enabled", false); /* 7020: disable WebRTC (Web Real-Time Communication) * [WHY] Firefox desktop uses mDNS hostname obfuscation and the private IP is never exposed until * required in TRUSTED scenarios; i.e. after you grant device (microphone or camera) access * [TEST] https://browserleaks.com/webrtc * [1] https://groups.google.com/g/discuss-webrtc/c/6stQXi72BEU/m/2FwZd24UAQAJ * [2] https://datatracker.ietf.org/doc/html/draft-ietf-mmusic-mdns-ice-candidates#section-3.1.1 ***/ // user_pref("media.peerconnection.enabled", false); /*** [SECTION 8000]: DON'T BOTHER: FINGERPRINTING [WHY] They are insufficient to help anti-fingerprinting and do more harm than good [WARNING] DO NOT USE with RFP. RFP already covers these and they can interfere ***/ user_pref("_user.js.parrot", "8000 syntax error: the parrot's crossed the Jordan"); /* 8001: prefsCleaner: reset items useless for anti-fingerprinting ***/ // user_pref("browser.display.use_document_fonts", ""); // user_pref("browser.zoom.siteSpecific", ""); // user_pref("device.sensors.enabled", ""); // user_pref("dom.enable_performance", ""); // user_pref("dom.enable_resource_timing", ""); // user_pref("dom.gamepad.enabled", ""); // user_pref("dom.maxHardwareConcurrency", ""); // user_pref("dom.w3c_touch_events.enabled", ""); // user_pref("dom.webaudio.enabled", ""); // user_pref("font.system.whitelist", ""); // user_pref("general.appname.override", ""); // user_pref("general.appversion.override", ""); // user_pref("general.buildID.override", ""); // user_pref("general.oscpu.override", ""); // user_pref("general.platform.override", ""); // user_pref("general.useragent.override", ""); // user_pref("media.navigator.enabled", ""); // user_pref("media.ondevicechange.enabled", ""); // user_pref("media.video_stats.enabled", ""); // user_pref("media.webspeech.synth.enabled", ""); // user_pref("ui.use_standins_for_native_colors", ""); // user_pref("webgl.enable-debug-renderer-info", ""); /*** [SECTION 9000]: NON-PROJECT RELATED ***/ user_pref("_user.js.parrot", "9000 syntax error: the parrot's cashed in 'is chips!"); /* 9001: disable welcome notices ***/ user_pref("browser.startup.homepage_override.mstone", "ignore"); // [HIDDEN PREF] /* 9002: disable General>Browsing>Recommend extensions/features as you browse [FF67+] ***/ user_pref("browser.newtabpage.activity-stream.asrouter.userprefs.cfr.addons", false); user_pref("browser.newtabpage.activity-stream.asrouter.userprefs.cfr.features", false); /* 9003: disable What's New toolbar icon [FF69+] ***/ user_pref("browser.messaging-system.whatsNewPanel.enabled", false); /* 9004: disable search terms [FF110+] * [SETTING] Search>Search Bar>Use the address bar for search and navigation>Show search terms instead of URL... ***/ user_pref("browser.urlbar.showSearchTerms.enabled", false); /*** [SECTION 9999]: DEPRECATED / RENAMED ***/ user_pref("_user.js.parrot", "9999 syntax error: the parrot's shuffled off 'is mortal coil!"); /* ESR115.x still uses all the following prefs // [NOTE] replace the * with a slash in the line above to re-enable active ones // FF116 // 4506: set RFP's font visibility level (1402) [FF94+] // [-] https://bugzilla.mozilla.org/1838415 // user_pref("layout.css.font-visibility.resistFingerprinting", 1); // [DEFAULT: 1] // FF117 // 1221: disable Windows Microsoft Family Safety cert [FF50+] [WINDOWS] // 0=disable detecting Family Safety mode and importing the root // 1=only attempt to detect Family Safety mode (don't import the root) // 2=detect Family Safety mode and import the root // [1] https://gitlab.torproject.org/tpo/applications/tor-browser/-/issues/21686 // [-] https://bugzilla.mozilla.org/1844908 user_pref("security.family_safety.mode", 0); // 7018: disable service worker Web Notifications [FF44+] // [WHY] Web Notifications are behind a prompt (7002) // [1] https://blog.mozilla.org/en/products/firefox/block-notification-requests/ // [-] https://bugzilla.mozilla.org/1842457 // user_pref("dom.webnotifications.serviceworker.enabled", false); // FF118 // 1402: limit font visibility (Windows, Mac, some Linux) [FF94+] // Uses hardcoded lists with two parts: kBaseFonts + kLangPackFonts [1], bundled fonts are auto-allowed // In normal windows: uses the first applicable: RFP over TP over Standard // In Private Browsing windows: uses the most restrictive between normal and private // 1=only base system fonts, 2=also fonts from optional language packs, 3=also user-installed fonts // [1] https://searchfox.org/mozilla-central/search?path=StandardFonts*.inc // [-] https://bugzilla.mozilla.org/1847599 // user_pref("layout.css.font-visibility.private", 1); // user_pref("layout.css.font-visibility.standard", 1); // user_pref("layout.css.font-visibility.trackingprotection", 1); // 2623: disable permissions delegation [FF73+] // Currently applies to cross-origin geolocation, camera, mic and screen-sharing // permissions, and fullscreen requests. Disabling delegation means any prompts // for these will show/use their correct 3rd party origin // [1] https://groups.google.com/forum/#!topic/mozilla.dev.platform/BdFOMAuCGW8/discussion // [-] https://bugzilla.mozilla.org/1697151 // user_pref("permissions.delegation.enabled", false); // FF119 // 0211: use en-US locale regardless of the system or region locale // [SETUP-WEB] May break some input methods e.g xim/ibus for CJK languages [1] // [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=867501,1629630 // [-] https://bugzilla.mozilla.org/1846224 // user_pref("javascript.use_us_english_locale", true); // [HIDDEN PREF] // 0711: disable skipping DoH when parental controls are enabled [FF70+] // [-] https://bugzilla.mozilla.org/1586941 user_pref("network.dns.skipTRR-when-parental-control-enabled", false); // ***/ /* END: internal custom pref to test for syntax errors ***/ user_pref("_user.js.parrot", "SUCCESS: No no he's not dead, he's, he's restin'!"); user_pref("browser.tabs.firefox-view", false); user_pref("browser.tabs.firefox-view-next", false); user_pref("browser.tabs.warnOnClose", true); user_pref("browser.toolbars.bookmarks.visibility", "never"); user_pref("browser.translations.automaticallyPopup", false); user_pref("browser.promo.focus.enabled", false); user_pref("browser.promo.pin.enabled", false); user_pref("browser.vpn_promo.enabled", false); user_pref("extensions.pocket.enabled", false); user_pref("full-screen-api.warning.delay", 0); user_pref("full-screen-api.warning.timeout", 0); user_pref("full-screen-api.transition.timeout", 0); user_pref("general.smoothScroll", false); user_pref("general.smoothScroll.lines", false); user_pref("general.smoothScroll.mouseWheel", false); user_pref("general.smoothScroll.other", false); user_pref("general.smoothScroll.pages", false); user_pref("general.smoothScroll.pixels", false); user_pref("general.smoothScroll.scrollbars", false); user_pref("toolkit.scrollbox.smoothScroll", false); user_pref("layout.spellcheckDefault", 0); user_pref("media.autoplay.default", 5); user_pref("media.autoplay.blocking_policy", 2); user_pref("network.http.max-connections", 1800); user_pref("network.http.max-persistent-connections-per-proxy", 64); user_pref("network.http.max-persistent-connections-per-server", 12); user_pref("network.http.max-urgent-start-excessive-connections-per-host", 6); user_pref("network.websocket.max-connections", 400);