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|
/******
* name: arkenfox user.js
* date: 27 August 2023
* version: 115
* url: https://github.com/arkenfox/user.js
* 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
* It is best to use the arkenfox release that is optimized for and matches your Firefox version
* EVERYONE: each release
- run prefsCleaner to reset prefs made inactive, including deprecated (9999s)
ESR102
- If you are not using arkenfox v102-1... (not a definitive list)
- 2815: clearOnShutdown cookies + offlineApps should be false
- 9999: switch the appropriate deprecated section(s) back on
* INDEX:
0100: STARTUP
0200: GEOLOCATION / LANGUAGE / LOCALE
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)
1400: FONTS
1700: CONTAINERS
2000: PLUGINS / MEDIA / WEBRTC
2400: DOM (DOCUMENT OBJECT MODEL)
2600: MISCELLANEOUS
2700: ETP (ENHANCED TRACKING PROTECTION)
2800: SHUTDOWN & SANITIZING
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 / REMOVED / LEGACY / 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 / LANGUAGE / LOCALE ***/
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]
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);
/** 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://gitlab.torproject.org/tpo/applications/tor-browser/-/issues/26424 ***/
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. By default only sftp is accepted (FF87+)
* [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]
/* 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: disable DNS-over-HTTPS (DoH) rollout [FF60+]
* 0=default, 2=increased (TRR (Trusted Recursive Resolver) first), 3=max (TRR only), 5=off
* 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);
/*** [SECTION 0800]: LOCATION BAR / SEARCH BAR / SUGGESTIONS / HISTORY / FORMS ***/
user_pref("_user.js.parrot", "0800 syntax error: the parrot's ceased to be!");
/* 0802: disable location bar domain guessing
* domain guessing intercepts DNS "hostname not found errors" and resends a
* request (e.g. by adding www or .com). This is inconsistent use (e.g. FQDNs), does not work
* via Proxy Servers (different error), is a flawed use of DNS (TLDs: why treat .com
* as the 411 for DNS errors?), privacy issues (why connect to sites you didn't
* intend to), can leak sensitive data (e.g. query strings: e.g. Princeton attack),
* and is a security risk (e.g. common typos & malicious sites set up to exploit this) ***/
user_pref("browser.fixup.alternate.enabled", false); // [DEFAULT: false FF104+]
/* 0804: 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 location bar making speculative connections [FF56+]
* [1] https://bugzilla.mozilla.org/1348275 ***/
user_pref("browser.urlbar.speculativeConnect.enabled", false);
/* 0806: disable location bar leaking single words to a DNS provider **after searching** [FF78+]
* 0=never resolve, 1=use heuristics, 2=always resolve
* [1] https://bugzilla.mozilla.org/1642623 ***/
user_pref("browser.urlbar.dnsResolveSingleWordsAfterSearch", 0); // [DEFAULT: 0 FF104+]
/* 0807: disable location bar contextual suggestions [FF92+]
* [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);
/* 0808: 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);
/* 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);
/* 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);
/*** [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
* 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 (Feb 2023) reports over 99.3% 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) ***/
/* 1221: disable Windows 8.1's 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 ***/
user_pref("security.family_safety.mode", 0);
/* 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" (FF99+, default FF100+)
* [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 [FF76+]
* 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 1400]: FONTS ***/
user_pref("_user.js.parrot", "1400 syntax error: the parrot's bereft of life!");
/* 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 (4506) 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 ***/
// user_pref("layout.css.font-visibility.private", 1);
// user_pref("layout.css.font-visibility.standard", 1);
// user_pref("layout.css.font-visibility.trackingprotection", 1);
/*** [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!");
/* 2601: prevent accessibility services from accessing your browser [RESTART]
* [1] https://support.mozilla.org/kb/accessibility-services ***/
user_pref("accessibility.force_disabled", 1);
/* 2603: remove temp files opened with an external application
* [1] https://bugzilla.mozilla.org/302433 ***/
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+]
/* 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 ***/
user_pref("permissions.delegation.enabled", false);
/* 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");
/* 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);
/* 2710: enable state partitioning of service workers [FF96+] ***/
user_pref("privacy.partition.serviceWorkers", true); // [DEFAULT: true FF105+]
/* 2720: enable APS (Always Partitioning Storage) ***/
user_pref("privacy.partition.always_partition_third_party_non_cookie_storage", true); // [FF104+] [DEFAULT: true FF109+]
user_pref("privacy.partition.always_partition_third_party_non_cookie_storage.exempt_sessionstorage", false); // [FF105+] [DEFAULT: false FF109+]
/*** [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 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);
/* 5015: disable Windows taskbar preview [WINDOWS] ***/
// user_pref("browser.taskbar.previews.enable", false); // [DEFAULT: 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 crytopmining / 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.
* If you see PR_CONNECT_RESET_ERROR, this pref *might* be the cause
* [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);
/*** [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 [FF81+]
* In FF96+ these are listed in about:compat
* [1] https://blog.mozilla.org/security/2021/03/23/introducing-smartblock/ ***/
user_pref("extensions.webcompat.enable_shims", true); // [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: reset previously active items removed from arkenfox FF102+ ***/
// user_pref("beacon.enabled", "");
// user_pref("browser.startup.blankWindow", "");
// user_pref("browser.newtab.preload", "");
// user_pref("browser.newtabpage.activity-stream.feeds.discoverystreamfeed", "");
// user_pref("browser.newtabpage.activity-stream.feeds.snippets", "");
// user_pref("browser.region.network.url", "");
// user_pref("browser.region.update.enabled", "");
// user_pref("browser.ssl_override_behavior", "");
// user_pref("devtools.chrome.enabled", "");
// user_pref("dom.disable_beforeunload", "");
// user_pref("dom.disable_open_during_load", "");
// user_pref("extensions.formautofill.available", "");
// user_pref("extensions.formautofill.addresses.supported", "");
// user_pref("extensions.formautofill.creditCards.available", "");
// user_pref("extensions.formautofill.creditCards.supported", "");
// user_pref("middlemouse.contentLoadURL", "");
/* 6051: prefsCleaner: reset previously active items removed from arkenfox FF115+ ***/
// user_pref("network.protocol-handler.external.ms-windows-store", "");
/*** [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); // [DEFAULT: false FF109+]
// user_pref("security.ssl3.ecdhe_ecdsa_aes_256_sha", false); // [DEFAULT: false FF109+]
// 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
* [WHY] Arkenfox only supports strict (2701) which sets these at runtime ***/
// user_pref("network.cookie.cookieBehavior", 5); // [DEFAULT: 5 FF103+]
// 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);
// user_pref("privacy.query_stripping.enabled", true); // [FF101+] [ETP FF102+]
// 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
* [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); // [FF22+]
// user_pref("dom.webnotifications.serviceworker.enabled", false); // [FF44+]
/* 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");
/* 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 / REMOVED / LEGACY / RENAMED
Documentation denoted as [-]. Items deprecated prior to FF91 have been archived at [1]
[1] https://github.com/arkenfox/user.js/issues/123
***/
user_pref("_user.js.parrot", "9999 syntax error: the parrot's shuffled off 'is mortal coil!");
/* ESR102.x still uses all the following prefs
// [NOTE] replace the * with a slash in the line above to re-enable active ones
// FF103
// 2801: delete cookies and site data on exit - replaced by sanitizeOnShutdown* (2810)
// 0=keep until they expire (default), 2=keep until you close Firefox
// [SETTING] Privacy & Security>Cookies and Site Data>Delete cookies and site data when Firefox is closed
// [-] https://bugzilla.mozilla.org/buglist.cgi?bug_id=1681493,1681495,1681498,1759665,1764761
user_pref("network.cookie.lifetimePolicy", 2);
// 6012: disable SHA-1 certificates
// [-] https://bugzilla.mozilla.org/1766687
// user_pref("security.pki.sha1_enforcement_level", 1); // [DEFAULT: 1]
// FF114
// 2816: set cache to clear on exit [FF96+]
// [NOTE] We already disable disk cache (1001) and clear on exit (2811) which is more robust
// [1] https://bugzilla.mozilla.org/1671182
// [-] https://bugzilla.mozilla.org/1821651
// user_pref("privacy.clearsitedata.cache.enabled", true);
// 4505: experimental RFP [FF91+]
// [-] https://bugzilla.mozilla.org/1824235
// user_pref("privacy.resistFingerprinting.testGranularityMask", 0);
// 5017: disable Form Autofill heuristics
// Heuristics controls Form Autofill on forms without @autocomplete attributes
// [-] https://bugzilla.mozilla.org/1829670
// user_pref("extensions.formautofill.heuristics.enabled", false); // [FF55+]
// FF115
// 7001: disable offline cache (appCache)
// [NOTE] appCache storage capability was removed in FF90
// [-] https://bugzilla.mozilla.org/1677718
// user_pref("browser.cache.offline.enable", 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.warnOnClose", true);
user_pref("browser.toolbars.bookmarks.visibility", "never");
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);
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