Adding arkenfox user.js version 126.1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 812 insertions, 77 deletions

diff --git a/debian/local/pref/user.js b/debian/local/pref/user.js
index 42873333b1..8087d85047 100644
--- a/debian/local/pref/user.js
+++ b/debian/local/pref/user.js
@@ -1,11 +1,42 @@
 /******
 *    name: arkenfox user.js
-*    date: 5 February 2024
-* version: 122
+*    date: 7 June 2024
+* version: 126
 *    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 you - also see section 9999
+
 * INDEX:
 
   0100: STARTUP
@@ -16,26 +47,44 @@
   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)
+  1600: REFERERS
   1700: CONTAINERS
+  2000: PLUGINS / MEDIA / WEBRTC
   2400: DOM (DOCUMENT OBJECT MODEL)
   2600: MISCELLANEOUS
   2700: ETP (ENHANCED TRACKING PROTECTION)
   2800: SHUTDOWN & SANITIZING
+  4000: FPP (fingerprintingProtection)
+  4500: RFP (resistFingerprinting)
   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);
+user_pref("browser.startup.page", 0);
 /* 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 ***/
@@ -46,21 +95,26 @@ user_pref("browser.startup.homepage", "about:blank");
 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
+user_pref("browser.newtabpage.activity-stream.showSponsored", false); // [FF58+]
+user_pref("browser.newtabpage.activity-stream.showSponsoredTopSites", false); // [FF83+] Shortcuts>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]
@@ -104,9 +158,6 @@ user_pref("toolkit.telemetry.firstShutdownPing.enabled", false); // [FF57+]
 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);
@@ -125,6 +176,7 @@ user_pref("app.normandy.api_url", "");
 /* 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]
@@ -149,39 +201,42 @@ user_pref("network.connectivity-service.enabled", false);
    [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);
+   // 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);
+   // 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
+   // 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);
+   // 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);
+   // user_pref("browser.safebrowsing.allowOverride", false);
 
 /*** [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]
@@ -190,8 +245,12 @@ user_pref("network.predictor.enable-prefetch", false); // [FF48+] [DEFAULT: fals
 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
@@ -208,6 +267,17 @@ user_pref("network.file.disable_unc_paths", true); // [HIDDEN PREF]
  * [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]
@@ -216,19 +286,28 @@ user_pref("network.gio.supported-protocols", ""); // [HIDDEN PREF] [DEFAULT: ""
  * [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);
+   // user_pref("network.trr.mode", 3);
+/* 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...
+ * [NOTE] The UI is controlled by the .enabled pref
+ * [SETTING] Search>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+]
+   // user_pref("browser.urlbar.quicksuggest.enabled", false); // [FF92+] [DEFAULT: false]
+   // user_pref("browser.urlbar.suggest.quicksuggest.nonsponsored", false); // [FF95+] [DEFAULT: false]
+   // user_pref("browser.urlbar.suggest.quicksuggest.sponsored", false); // [FF92+] [DEFAULT: false]
 /* 0803: disable live search suggestions
- * [NOTE] Both must be true for the location bar to work
+ * [NOTE] Both must be true for live search to work in the location bar
  * [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);
@@ -241,6 +320,9 @@ 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]
+user_pref("browser.urlbar.yelp.featureGate", false); // [FF124+] [DEFAULT: false]
+/* 0807: disable urlbar clipboard suggestions [FF118+] ***/
+   // user_pref("browser.urlbar.clipboard.featureGate", 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)
@@ -250,8 +332,19 @@ user_pref("browser.urlbar.weather.featureGate", false); // [FF108+] [DEFAULT: fa
 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);
+ * [SETTING] Search>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+]
@@ -260,6 +353,7 @@ 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
@@ -275,6 +369,33 @@ user_pref("signon.formlessCapture.enabled", false);
  * 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!");
+/* 1001: disable disk cache
+ * [SETUP-CHROME] If you think disk cache helps perf, then feel free to override this
+ * [NOTE] We also clear cache on exit (2811) ***/
+user_pref("browser.cache.disk.enable", false);
+/* 1002: disable media cache from writing to disk in Private Browsing
+ * [NOTE] MSE (Media Source Extensions) are already stored in-memory in PB ***/
+user_pref("browser.privatebrowsing.forceMediaMemoryCache", true); // [FF75+]
+user_pref("media.memory_cache_max_size", 65536);
+/* 1003: disable storing extra session data [SETUP-CHROME]
+ * define on which sites to save extra session data such as form content, cookies and POST data
+ * 0=everywhere, 1=unencrypted sites, 2=nowhere ***/
+user_pref("browser.sessionstore.privacy_level", 2);
+/* 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
@@ -283,6 +404,7 @@ user_pref("network.auth.subresource-http-auth-allow", 1);
    [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
@@ -290,7 +412,7 @@ user_pref("network.auth.subresource-http-auth-allow", 1);
  * 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]
+ * [STATS] SSL Labs (May 2024) reports over 99.7% 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
@@ -342,6 +464,8 @@ 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")
@@ -349,6 +473,9 @@ user_pref("security.pki.crlite_mode", 2);
  * [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
@@ -368,27 +495,73 @@ user_pref("security.ssl.treat_unsafe_negotiation_as_broken", true);
  * [TEST] https://expired.badssl.com/ ***/
 user_pref("browser.xul.error_pages.expert_bad_cert", true);
 
+/*** [SECTION 1600]: REFERERS
+                  full URI: https://example.com:8888/foo/bar.html?id=1234
+     scheme+host+port+path: https://example.com:8888/foo/bar.html
+          scheme+host+port: https://example.com:8888
+   [1] https://feeding.cloud.geek.nz/posts/tweaking-referrer-for-privacy-in-firefox/
+***/
+user_pref("_user.js.parrot", "1600 syntax error: the parrot rests in peace!");
+/* 1602: control the amount of cross-origin information to send [FF52+]
+ * 0=send full URI (default), 1=scheme+host+port+path, 2=scheme+host+port ***/
+user_pref("network.http.referer.XOriginTrimmingPolicy", 2);
+
 /*** [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);
+/* 1703: set external links to open in site-specific containers [FF123+]
+ * [SETUP-WEB] Depending on your container extension(s) and their settings
+ * true=Firefox will not choose a container (so your extension can)
+ * false=Firefox will choose the container/no-container (default)
+ * [1] https://bugzilla.mozilla.org/1874599 ***/
+   // user_pref("browser.link.force_default_user_context_id_for_external_opens", true);
+
+/*** [SECTION 2000]: PLUGINS / MEDIA / WEBRTC ***/
+user_pref("_user.js.parrot", "2000 syntax error: the parrot's snuffed it!");
+/* 2002: force WebRTC inside the proxy [FF70+] ***/
+user_pref("media.peerconnection.ice.proxy_only_if_behind_proxy", true);
+/* 2003: force a single network interface for ICE candidates generation [FF42+]
+ * When using a system-wide proxy, it uses the proxy interface
+ * [1] https://developer.mozilla.org/en-US/docs/Web/API/RTCIceCandidate
+ * [2] https://wiki.mozilla.org/Media/WebRTC/Privacy ***/
+user_pref("media.peerconnection.ice.default_address_only", true);
+/* 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", "");
@@ -416,8 +589,17 @@ 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]
+/* 2630: disable content analysis by DLP (Data Loss Prevention) agents
+ * DLP agents are background processes on managed computers that allow enterprises to monitor locally running
+ * applications for data exfiltration events, which they can allow/block based on customer defined DLP policies.
+ * [1] https://github.com/chromium/content_analysis_sdk */
+user_pref("browser.contentanalysis.default_allow", false); // [FF124+] [DEFAULT: false]
 
 /** DOWNLOADS ***/
+/* 2651: enable user interaction for security by always asking where to download
+ * [SETUP-CHROME] On Android this blocks longtapping and saving images
+ * [SETTING] General>Downloads>Always ask you where to save files ***/
+user_pref("browser.download.useDownloadDir", false);
 /* 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 ***/
@@ -427,11 +609,22 @@ user_pref("browser.download.manager.addToRecentDocs", false);
 user_pref("browser.download.always_ask_before_handling_new_types", true);
 
 /** EXTENSIONS ***/
+/* 2660: limit allowed extension directories
+ * 1=profile, 2=user, 4=application, 8=system, 16=temporary, 31=all
+ * The pref value represents the sum: e.g. 5 would be profile and application directories
+ * [SETUP-CHROME] Breaks usage of files which are installed outside allowed directories
+ * [1] https://archive.is/DYjAM ***/
+user_pref("extensions.enabledScopes", 5); // [HIDDEN PREF]
+   // user_pref("extensions.autoDisableScopes", 15); // [DEFAULT: 15]
 /* 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
@@ -440,93 +633,635 @@ user_pref("extensions.postDownloadThirdPartyPrompt", false);
  * [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 ***/
-/** 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
+user_pref("_user.js.parrot", "2800 syntax error: the parrot's bleedin' demised!");
+/* 2810: enable Firefox to clear items on shutdown
+ * [SETTING] Privacy & Security>History>Custom Settings>Clear history when Firefox closes | Settings ***/
+user_pref("privacy.sanitize.sanitizeOnShutdown", true);
+
+/** SANITIZE ON SHUTDOWN: IGNORES "ALLOW" SITE EXCEPTIONS | v2 migration is FF128+ ***/
+/* 2811: set/enforce what items to clear on shutdown (if 2810 is true) [SETUP-CHROME]
+ * [NOTE] If "history" is true, downloads will also be cleared ***/
+user_pref("privacy.clearOnShutdown.cache", true);     // [DEFAULT: true]
+user_pref("privacy.clearOnShutdown_v2.cache", true);  // [FF128+] [DEFAULT: true]
+user_pref("privacy.clearOnShutdown.downloads", true); // [DEFAULT: true]
+user_pref("privacy.clearOnShutdown.formdata", true);  // [DEFAULT: true]
+user_pref("privacy.clearOnShutdown.history", true);   // [DEFAULT: true]
+user_pref("privacy.clearOnShutdown_v2.historyFormDataAndDownloads", true); // [FF128+] [DEFAULT: true]
+   // user_pref("privacy.clearOnShutdown.siteSettings", false); // [DEFAULT: false]
+   // user_pref("privacy.clearOnShutdown_v2.siteSettings", false); // [FF128+] [DEFAULT: false]
+/* 2812: set Session Restore to clear on shutdown (if 2810 is true) [FF34+]
+ * [NOTE] Not needed if Session Restore is not used (0102) or it is already cleared with history (2811)
+ * [NOTE] If true, this prevents resuming from crashes (also see 5008) ***/
+   // user_pref("privacy.clearOnShutdown.openWindows", true);
+
+/** SANITIZE ON SHUTDOWN: RESPECTS "ALLOW" SITE EXCEPTIONS FF103+ | v2 migration is FF128+ ***/
+/* 2815: set "Cookies" and "Site Data" to clear on shutdown (if 2810 is true) [SETUP-CHROME]
+ * [NOTE] Exceptions: A "cookie" block permission also controls "offlineApps" (see note below).
+ * serviceWorkers require an "Allow" permission. For cross-domain logins, add exceptions for
+ * both sites e.g. https://www.youtube.com (site) + https://accounts.google.com (single sign on)
+ * [NOTE] "offlineApps": Offline Website Data: localStorage, service worker cache, QuotaManager (IndexedDB, asm-cache)
+ * [NOTE] "sessions": Active Logins (has no site exceptions): refers to HTTP Basic Authentication [1], not logins via cookies
+ * [WARNING] Be selective with what sites you "Allow", as they also disable partitioning (1767271)
+ * [SETTING] to add site exceptions: Ctrl+I>Permissions>Cookies>Allow (when on the website in question)
+ * [SETTING] to manage site exceptions: Options>Privacy & Security>Permissions>Settings
+ * [1] https://en.wikipedia.org/wiki/Basic_access_authentication ***/
+user_pref("privacy.clearOnShutdown.cookies", true); // Cookies
+user_pref("privacy.clearOnShutdown.offlineApps", true); // Site Data
+user_pref("privacy.clearOnShutdown.sessions", true);  // Active Logins [DEFAULT: true]
+user_pref("privacy.clearOnShutdown_v2.cookiesAndStorage", true); // Cookies, Site Data, Active Logins [FF128+]
+
+/** SANITIZE SITE DATA: IGNORES "ALLOW" SITE EXCEPTIONS ***/
+/* 2820: set manual "Clear Data" items [SETUP-CHROME] [FF128+]
+ * Firefox remembers your last choices. This will reset them when you start Firefox
+ * [SETTING] Privacy & Security>Browser Privacy>Cookies and Site Data>Clear Data ***/
+user_pref("privacy.clearSiteData.cache", true);
+user_pref("privacy.clearSiteData.cookiesAndStorage", false); // keep false until it respects "allow" site exceptions
+user_pref("privacy.clearSiteData.historyFormDataAndDownloads", true);
+   // user_pref("privacy.clearSiteData.siteSettings", false);
+
+/** SANITIZE HISTORY: IGNORES "ALLOW" SITE EXCEPTIONS | clearHistory migration is FF128+ ***/
+/* 2830: set manual "Clear History" items, also via Ctrl-Shift-Del [SETUP-CHROME]
  * 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" ***/
+ * for "Clear Recent History" is opened, it is synced to the same as "history"
+ * [SETTING] Privacy & Security>History>Custom Settings>Clear History ***/
 user_pref("privacy.cpd.cache", true);    // [DEFAULT: true]
+user_pref("privacy.clearHistory.cache", true);
 user_pref("privacy.cpd.formdata", true); // [DEFAULT: true]
 user_pref("privacy.cpd.history", true);  // [DEFAULT: true]
+   // user_pref("privacy.cpd.downloads", true); // not used, see note above
+user_pref("privacy.clearHistory.historyFormDataAndDownloads", true);
+user_pref("privacy.cpd.cookies", false);
 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.siteSettings", true);
-/* 2822: reset default "Time range to clear" for "Clear Recent History" (2820)
+user_pref("privacy.clearHistory.cookiesAndStorage", false);
+   // user_pref("privacy.cpd.openWindows", false); // Session Restore
+   // user_pref("privacy.cpd.passwords", false);
+   // user_pref("privacy.cpd.siteSettings", false);
+   // user_pref("privacy.clearHistory.siteSettings", false);
+
+/** SANITIZE MANUAL: TIMERANGE ***/
+/* 2840: set "Time range to clear" for "Clear Data" (2820) and "Clear History" (2830)
  * 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);
+user_pref("privacy.sanitize.timeSpan", 0);
+
+/*** [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 (4003).
+
+   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", "4000 syntax error: the parrot's bereft of life!");
+/* 4001: enable FPP in PB mode [FF114+]
+ * [NOTE] In FF119+, FPP for all modes (7016) 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", "");
+/* 4003: disable remote FPP overrides [FF127+] ***/
+   // user_pref("privacy.fingerprintingProtection.remoteOverrides.enabled", false);
+
+/*** [SECTION 4500]: RFP (resistFingerprinting)
+   RFP overrides FPP (4000)
+
+   It is an all-or-nothing buy in: you cannot pick and choose what parts you want
+   [TEST] https://arkenfox.github.io/TZP/tzp.html
+
+   [WARNING] DO NOT USE extensions to alter RFP protected metrics
+
+    418986 - limit window.screen & CSS media queries (FF41)
+   1281949 - spoof screen orientation (FF50)
+   1360039 - spoof navigator.hardwareConcurrency as 2 (FF55)
+ FF56
+   1333651 - spoof User Agent & Navigator API
+      version: android version spoofed as ESR (FF119 or lower)
+      OS: JS spoofed as Windows 10, OS 10.15, Android 10, or Linux | HTTP Headers spoofed as Windows or Android
+   1369319 - disable device sensor API
+   1369357 - disable site specific zoom
+   1337161 - hide gamepads from content
+   1372072 - spoof network information API as "unknown" when dom.netinfo.enabled = true
+   1333641 - reduce fingerprinting in WebSpeech API
+ FF57
+   1369309 - spoof media statistics
+   1382499 - reduce screen co-ordinate fingerprinting in Touch API
+   1217290 & 1409677 - enable some fingerprinting resistance for WebGL
+   1354633 - limit MediaError.message to a whitelist
+ FF58+
+   1372073 - spoof/block fingerprinting in MediaDevices API (FF59)
+      Spoof: enumerate devices as one "Internal Camera" and one "Internal Microphone"
+      Block: suppresses the ondevicechange event
+   1039069 - warn when language prefs are not set to "en*" (FF59)
+   1222285 & 1433592 - spoof keyboard events and suppress keyboard modifier events (FF59)
+      Spoofing mimics the content language of the document. Currently it only supports en-US.
+      Modifier events suppressed are SHIFT and both ALT keys. Chrome is not affected.
+   1337157 - disable WebGL debug renderer info (FF60)
+   1459089 - disable OS locale in HTTP Accept-Language headers (ANDROID) (FF62)
+   1479239 - return "no-preference" with prefers-reduced-motion (FF63)
+   1363508 - spoof/suppress Pointer Events (FF64)
+   1492766 - spoof pointerEvent.pointerid (FF65)
+   1485266 - disable exposure of system colors to CSS or canvas (FF67)
+   1494034 - return "light" with prefers-color-scheme (FF67)
+   1564422 - spoof audioContext outputLatency (FF70)
+   1595823 - return audioContext sampleRate as 44100 (FF72)
+   1607316 - spoof pointer as coarse and hover as none (ANDROID) (FF74)
+   1621433 - randomize canvas (previously FF58+ returned an all-white canvas) (FF78)
+   1506364 - return "no-preference" with prefers-contrast (FF80)
+   1653987 - limit font visibility to bundled and "Base Fonts" (Windows, Mac, some Linux) (FF80)
+   1461454 - spoof smooth=true and powerEfficient=false for supported media in MediaCapabilities (FF82)
+    531915 - use fdlibm's sin, cos and tan in jsmath (FF93, ESR91.1)
+   1756280 - enforce navigator.pdfViewerEnabled as true and plugins/mimeTypes as hard-coded values (FF100-115)
+   1692609 - reduce JS timing precision to 16.67ms (previously FF55+ was 100ms) (FF102)
+   1422237 - return "srgb" with color-gamut (FF110)
+   1794628 - return "none" with inverted-colors (FF114)
+   1554751 - return devicePixelRatio as 2 (previously FF41+ was 1) (FF127)
+   1787790 - normalize system fonts (FF128)
+   1835987 - spoof timezone as Atlantic/Reykjavik (previously FF55+ was UTC) (FF128)
+***/
+user_pref("_user.js.parrot", "4500 syntax error: the parrot's popped 'is clogs");
+/* 4501: enable RFP
+ * [SETUP-WEB] RFP can cause some website breakage: mainly canvas, use a canvas site exception via the urlbar.
+ * RFP also has a few side effects: mainly timezone is UTC, and websites will prefer light theme
+ * [NOTE] pbmode applies if true and the original pref is false
+ * [1] https://bugzilla.mozilla.org/418986 ***/
+user_pref("privacy.resistFingerprinting", true); // [FF41+]
+   // user_pref("privacy.resistFingerprinting.pbmode", true); // [FF114+]
+/* 4502: set new window size rounding max values [FF55+]
+ * [SETUP-CHROME] sizes round down in hundreds: width to 200s and height to 100s, to fit your screen
+ * [1] https://bugzilla.mozilla.org/1330882 ***/
+user_pref("privacy.window.maxInnerWidth", 1600);
+user_pref("privacy.window.maxInnerHeight", 900);
+/* 4503: disable mozAddonManager Web API [FF57+]
+ * [NOTE] To allow extensions to work on AMO, you also need 2662
+ * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=1384330,1406795,1415644,1453988 ***/
+user_pref("privacy.resistFingerprinting.block_mozAddonManager", true);
+/* 4504: enable RFP letterboxing [FF67+]
+ * Dynamically resizes the inner window by applying margins in stepped ranges [2]
+ * If you use the dimension pref, then it will only apply those resolutions.
+ * The format is "width1xheight1, width2xheight2, ..." (e.g. "800x600, 1000x1000")
+ * [SETUP-WEB] This is independent of RFP (4501). If you're not using RFP, or you are but
+ * dislike the margins, then flip this pref, keeping in mind that it is effectively fingerprintable
+ * [WARNING] DO NOT USE: the dimension pref is only meant for testing
+ * [1] https://bugzilla.mozilla.org/1407366
+ * [2] https://hg.mozilla.org/mozilla-central/rev/6d2d7856e468#l2.32 ***/
+user_pref("privacy.resistFingerprinting.letterboxing", true); // [HIDDEN PREF]
+   // user_pref("privacy.resistFingerprinting.letterboxing.dimensions", ""); // [HIDDEN PREF]
+/* 4505: experimental RFP [FF91+]
+ * [WARNING] DO NOT USE unless testing, see [1] comment 12
+ * [1] https://bugzilla.mozilla.org/1635603 ***/
+   // user_pref("privacy.resistFingerprinting.exemptedDomains", "*.example.invalid");
+/* 4506: disable RFP spoof english prompt [FF59+]
+ * 0=prompt, 1=disabled, 2=enabled (requires RFP)
+ * [NOTE] When changing from value 2, preferred languages ('intl.accept_languages') is not reset.
+ * [SETUP-WEB] when enabled, sets 'en-US, en' for displaying pages and 'en-US' as locale.
+ * [SETTING] General>Language>Choose your preferred language for displaying pages>Choose>Request English... ***/
+user_pref("privacy.spoof_english", 1);
+/* 4510: disable using system colors
+ * [SETTING] General>Language and Appearance>Fonts and Colors>Colors>Use system colors ***/
+user_pref("browser.display.use_system_colors", false); // [DEFAULT: false NON-WINDOWS]
+/* 4511: enforce non-native widget theme
+ * Security: removes/reduces system API calls, e.g. win32k API [1]
+ * Fingerprinting: provides a uniform look and feel across platforms [2]
+ * [1] https://bugzilla.mozilla.org/1381938
+ * [2] https://bugzilla.mozilla.org/1411425 ***/
+user_pref("widget.non-native-theme.enabled", true); // [DEFAULT: true]
+/* 4512: enforce links targeting new windows to open in a new tab instead
+ * 1=most recent window or tab, 2=new window, 3=new tab
+ * Stops malicious window sizes and some screen resolution leaks.
+ * You can still right-click a link and open in a new window
+ * [SETTING] General>Tabs>Open links in tabs instead of new windows
+ * [TEST] https://arkenfox.github.io/TZP/tzp.html#screen
+ * [1] https://gitlab.torproject.org/tpo/applications/tor-browser/-/issues/9881 ***/
+user_pref("browser.link.open_newwindow", 3); // [DEFAULT: 3]
+/* 4513: set all open window methods to abide by "browser.link.open_newwindow" (4512)
+ * [1] https://searchfox.org/mozilla-central/source/dom/tests/browser/browser_test_new_window_from_content.js ***/
+user_pref("browser.link.open_newwindow.restriction", 0);
+/* 4520: disable WebGL (Web Graphics Library)
+ * [SETUP-WEB] If you need it then override it. RFP still randomizes canvas for naive scripts ***/
+user_pref("webgl.disabled", true);
 
 /*** [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] Search>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");
+   // user_pref("dom.popup_allowed_events", "click dblclick mousedown pointerdown");
 /* 5019: disable page thumbnail collection ***/
-user_pref("browser.pagethumbnails.capturing_disabled", true); // [HIDDEN PREF]
+   // 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);
+   // 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] Website "push" requires subscription, and the API is required for CRLite (1224)
+ * [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);
+/* 7021: enable GPC (Global Privacy Control) in non-PB windows
+ * [WHY] Passive and active fingerprinting. Mostly redundant with Tracking Protection
+ * in ETP Strict (2701) and sanitizing on close (2800s) ***/
+   // user_pref("privacy.globalprivacycontrol.enabled", true);
+
+/*** [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);
 
-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);
-
-user_pref("privacy.donottrackheader.enabled", true);
+/*** [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);
+// FF123
+// 0334: disable PingCentre telemetry (used in several System Add-ons) [FF57+]
+   // Defense-in-depth: currently covered by 0331
+   // [-] https://bugzilla.mozilla.org/1868988
+user_pref("browser.ping-centre.telemetry", false);
+// FF126
+// 9003: disable What's New toolbar icon [FF69+]
+   // [-] https://bugzilla.mozilla.org/1724300
+user_pref("browser.messaging-system.whatsNewPanel.enabled", false);
+// ***/
 
-user_pref("signon.management.page.fileImport.enabled", true);
+/* 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'!");