user.js

mirror of https://github.com/arkenfox/user.js
Log | Files | Refs | README

user.js (79705B)


      1 /******
      2 *    name: arkenfox user.js
      3 *    date: 7 June 2024
      4 * version: 126
      5 *    urls: https://github.com/arkenfox/user.js [repo]
      6 *        : https://arkenfox.github.io/gui/ [interactive]
      7 * license: MIT: https://github.com/arkenfox/user.js/blob/master/LICENSE.txt
      8 
      9 * README:
     10 
     11   1. Consider using Tor Browser if it meets your needs or fits your threat model
     12        * https://2019.www.torproject.org/about/torusers.html
     13   2. Read the entire wiki
     14        * https://github.com/arkenfox/user.js/wiki
     15   3. If you skipped step 2, return to step 2
     16   4. Make changes in a user-overrides.js
     17        * There are often trade-offs and conflicts between security vs privacy vs anti-tracking
     18          and these need to be balanced against functionality & convenience & breakage
     19        * Some site breakage and unintended consequences will happen. Everyone's experience will differ
     20          e.g. some user data is erased on exit (section 2800), change this to suit your needs
     21        * While not 100% definitive, search for "[SETUP" tags
     22   5. Some tag info
     23        [SETUP-SECURITY] it's one item, read it
     24             [SETUP-WEB] can cause some websites to break
     25          [SETUP-CHROME] changes how Firefox itself behaves (i.e. not directly website related)
     26   6. Override Recipes: https://github.com/arkenfox/user.js/issues/1080
     27 
     28 * RELEASES: https://github.com/arkenfox/user.js/releases
     29 
     30   * Use the arkenfox release that matches your Firefox version
     31     - DON'T wait for arkenfox to update Firefox, nothing major changes these days
     32   * Each release
     33     - run prefsCleaner to reset prefs made inactive, including deprecated (9999)
     34   * ESR
     35     - It is recommended to not use the updater, or you will get a later version which may cause issues.
     36       So you should manually append your overrides (and keep a copy), and manually update when you
     37       change ESR releases (arkenfox is already past that release)
     38     - If you decide to keep updating, then the onus is on you - also see section 9999
     39 
     40 * INDEX:
     41 
     42   0100: STARTUP
     43   0200: GEOLOCATION
     44   0300: QUIETER FOX
     45   0400: SAFE BROWSING
     46   0600: BLOCK IMPLICIT OUTBOUND
     47   0700: DNS / DoH / PROXY / SOCKS
     48   0800: LOCATION BAR / SEARCH BAR / SUGGESTIONS / HISTORY / FORMS
     49   0900: PASSWORDS
     50   1000: DISK AVOIDANCE
     51   1200: HTTPS (SSL/TLS / OCSP / CERTS / HPKP)
     52   1600: REFERERS
     53   1700: CONTAINERS
     54   2000: PLUGINS / MEDIA / WEBRTC
     55   2400: DOM (DOCUMENT OBJECT MODEL)
     56   2600: MISCELLANEOUS
     57   2700: ETP (ENHANCED TRACKING PROTECTION)
     58   2800: SHUTDOWN & SANITIZING
     59   4000: FPP (fingerprintingProtection)
     60   4500: RFP (resistFingerprinting)
     61   5000: OPTIONAL OPSEC
     62   5500: OPTIONAL HARDENING
     63   6000: DON'T TOUCH
     64   7000: DON'T BOTHER
     65   8000: DON'T BOTHER: FINGERPRINTING
     66   9000: NON-PROJECT RELATED
     67   9999: DEPRECATED / RENAMED
     68 
     69 ******/
     70 
     71 /* START: internal custom pref to test for syntax errors
     72  * [NOTE] Not all syntax errors cause parsing to abort i.e. reaching the last debug pref
     73  * no longer necessarily means that all prefs have been applied. Check the console right
     74  * after startup for any warnings/error messages related to non-applied prefs
     75  * [1] https://blog.mozilla.org/nnethercote/2018/03/09/a-new-preferences-parser-for-firefox/ ***/
     76 user_pref("_user.js.parrot", "START: Oh yes, the Norwegian Blue... what's wrong with it?");
     77 
     78 /* 0000: disable about:config warning ***/
     79 user_pref("browser.aboutConfig.showWarning", false);
     80 
     81 /*** [SECTION 0100]: STARTUP ***/
     82 user_pref("_user.js.parrot", "0100 syntax error: the parrot's dead!");
     83 /* 0102: set startup page [SETUP-CHROME]
     84  * 0=blank, 1=home, 2=last visited page, 3=resume previous session
     85  * [NOTE] Session Restore is cleared with history (2811), and not used in Private Browsing mode
     86  * [SETTING] General>Startup>Restore previous session ***/
     87 user_pref("browser.startup.page", 0);
     88 /* 0103: set HOME+NEWWINDOW page
     89  * about:home=Firefox Home (default, see 0105), custom URL, about:blank
     90  * [SETTING] Home>New Windows and Tabs>Homepage and new windows ***/
     91 user_pref("browser.startup.homepage", "about:blank");
     92 /* 0104: set NEWTAB page
     93  * true=Firefox Home (default, see 0105), false=blank page
     94  * [SETTING] Home>New Windows and Tabs>New tabs ***/
     95 user_pref("browser.newtabpage.enabled", false);
     96 /* 0105: disable sponsored content on Firefox Home (Activity Stream)
     97  * [SETTING] Home>Firefox Home Content ***/
     98 user_pref("browser.newtabpage.activity-stream.showSponsored", false); // [FF58+]
     99 user_pref("browser.newtabpage.activity-stream.showSponsoredTopSites", false); // [FF83+] Shortcuts>Sponsored shortcuts
    100 /* 0106: clear default topsites
    101  * [NOTE] This does not block you from adding your own ***/
    102 user_pref("browser.newtabpage.activity-stream.default.sites", "");
    103 
    104 /*** [SECTION 0200]: GEOLOCATION ***/
    105 user_pref("_user.js.parrot", "0200 syntax error: the parrot's definitely deceased!");
    106 /* 0201: use Mozilla geolocation service instead of Google if permission is granted [FF74+]
    107  * Optionally enable logging to the console (defaults to false) ***/
    108 user_pref("geo.provider.network.url", "https://location.services.mozilla.com/v1/geolocate?key=%MOZILLA_API_KEY%");
    109    // user_pref("geo.provider.network.logging.enabled", true); // [HIDDEN PREF]
    110 /* 0202: disable using the OS's geolocation service ***/
    111 user_pref("geo.provider.ms-windows-location", false); // [WINDOWS]
    112 user_pref("geo.provider.use_corelocation", false); // [MAC]
    113 user_pref("geo.provider.use_gpsd", false); // [LINUX] [HIDDEN PREF]
    114 user_pref("geo.provider.use_geoclue", false); // [FF102+] [LINUX]
    115 
    116 /*** [SECTION 0300]: QUIETER FOX ***/
    117 user_pref("_user.js.parrot", "0300 syntax error: the parrot's not pinin' for the fjords!");
    118 /** RECOMMENDATIONS ***/
    119 /* 0320: disable recommendation pane in about:addons (uses Google Analytics) ***/
    120 user_pref("extensions.getAddons.showPane", false); // [HIDDEN PREF]
    121 /* 0321: disable recommendations in about:addons' Extensions and Themes panes [FF68+] ***/
    122 user_pref("extensions.htmlaboutaddons.recommendations.enabled", false);
    123 /* 0322: disable personalized Extension Recommendations in about:addons and AMO [FF65+]
    124  * [NOTE] This pref has no effect when Health Reports (0331) are disabled
    125  * [SETTING] Privacy & Security>Firefox Data Collection & Use>Allow Firefox to make personalized extension recommendations
    126  * [1] https://support.mozilla.org/kb/personalized-extension-recommendations ***/
    127 user_pref("browser.discovery.enabled", false);
    128 /* 0323: disable shopping experience [FF116+]
    129  * [1] https://bugzilla.mozilla.org/show_bug.cgi?id=1840156#c0 ***/
    130 user_pref("browser.shopping.experience2023.enabled", false); // [DEFAULT: false]
    131 
    132 /** TELEMETRY ***/
    133 /* 0330: disable new data submission [FF41+]
    134  * If disabled, no policy is shown or upload takes place, ever
    135  * [1] https://bugzilla.mozilla.org/1195552 ***/
    136 user_pref("datareporting.policy.dataSubmissionEnabled", false);
    137 /* 0331: disable Health Reports
    138  * [SETTING] Privacy & Security>Firefox Data Collection & Use>Allow Firefox to send technical... data ***/
    139 user_pref("datareporting.healthreport.uploadEnabled", false);
    140 /* 0332: disable telemetry
    141  * The "unified" pref affects the behavior of the "enabled" pref
    142  * - If "unified" is false then "enabled" controls the telemetry module
    143  * - If "unified" is true then "enabled" only controls whether to record extended data
    144  * [NOTE] "toolkit.telemetry.enabled" is now LOCKED to reflect prerelease (true) or release builds (false) [2]
    145  * [1] https://firefox-source-docs.mozilla.org/toolkit/components/telemetry/telemetry/internals/preferences.html
    146  * [2] https://medium.com/georg-fritzsche/data-preference-changes-in-firefox-58-2d5df9c428b5 ***/
    147 user_pref("toolkit.telemetry.unified", false);
    148 user_pref("toolkit.telemetry.enabled", false); // see [NOTE]
    149 user_pref("toolkit.telemetry.server", "data:,");
    150 user_pref("toolkit.telemetry.archive.enabled", false);
    151 user_pref("toolkit.telemetry.newProfilePing.enabled", false); // [FF55+]
    152 user_pref("toolkit.telemetry.shutdownPingSender.enabled", false); // [FF55+]
    153 user_pref("toolkit.telemetry.updatePing.enabled", false); // [FF56+]
    154 user_pref("toolkit.telemetry.bhrPing.enabled", false); // [FF57+] Background Hang Reporter
    155 user_pref("toolkit.telemetry.firstShutdownPing.enabled", false); // [FF57+]
    156 /* 0333: disable Telemetry Coverage
    157  * [1] https://blog.mozilla.org/data/2018/08/20/effectively-measuring-search-in-firefox/ ***/
    158 user_pref("toolkit.telemetry.coverage.opt-out", true); // [HIDDEN PREF]
    159 user_pref("toolkit.coverage.opt-out", true); // [FF64+] [HIDDEN PREF]
    160 user_pref("toolkit.coverage.endpoint.base", "");
    161 /* 0335: disable Firefox Home (Activity Stream) telemetry ***/
    162 user_pref("browser.newtabpage.activity-stream.feeds.telemetry", false);
    163 user_pref("browser.newtabpage.activity-stream.telemetry", false);
    164 
    165 /** STUDIES ***/
    166 /* 0340: disable Studies
    167  * [SETTING] Privacy & Security>Firefox Data Collection & Use>Allow Firefox to install and run studies ***/
    168 user_pref("app.shield.optoutstudies.enabled", false);
    169 /* 0341: disable Normandy/Shield [FF60+]
    170  * Shield is a telemetry system that can push and test "recipes"
    171  * [1] https://mozilla.github.io/normandy/ ***/
    172 user_pref("app.normandy.enabled", false);
    173 user_pref("app.normandy.api_url", "");
    174 
    175 /** CRASH REPORTS ***/
    176 /* 0350: disable Crash Reports ***/
    177 user_pref("breakpad.reportURL", "");
    178 user_pref("browser.tabs.crashReporting.sendReport", false); // [FF44+]
    179    // user_pref("browser.crashReports.unsubmittedCheck.enabled", false); // [FF51+] [DEFAULT: false]
    180 /* 0351: enforce no submission of backlogged Crash Reports [FF58+]
    181  * [SETTING] Privacy & Security>Firefox Data Collection & Use>Allow Firefox to send backlogged crash reports  ***/
    182 user_pref("browser.crashReports.unsubmittedCheck.autoSubmit2", false); // [DEFAULT: false]
    183 
    184 /** OTHER ***/
    185 /* 0360: disable Captive Portal detection
    186  * [1] https://www.eff.org/deeplinks/2017/08/how-captive-portals-interfere-wireless-security-and-privacy ***/
    187 user_pref("captivedetect.canonicalURL", "");
    188 user_pref("network.captive-portal-service.enabled", false); // [FF52+]
    189 /* 0361: disable Network Connectivity checks [FF65+]
    190  * [1] https://bugzilla.mozilla.org/1460537 ***/
    191 user_pref("network.connectivity-service.enabled", false);
    192 
    193 /*** [SECTION 0400]: SAFE BROWSING (SB)
    194    SB has taken many steps to preserve privacy. If required, a full url is never sent
    195    to Google, only a part-hash of the prefix, hidden with noise of other real part-hashes.
    196    Firefox takes measures such as stripping out identifying parameters and since SBv4 (FF57+)
    197    doesn't even use cookies. (#Turn on browser.safebrowsing.debug to monitor this activity)
    198 
    199    [1] https://feeding.cloud.geek.nz/posts/how-safe-browsing-works-in-firefox/
    200    [2] https://wiki.mozilla.org/Security/Safe_Browsing
    201    [3] https://support.mozilla.org/kb/how-does-phishing-and-malware-protection-work
    202    [4] https://educatedguesswork.org/posts/safe-browsing-privacy/
    203 ***/
    204 user_pref("_user.js.parrot", "0400 syntax error: the parrot's passed on!");
    205 /* 0401: disable SB (Safe Browsing)
    206  * [WARNING] Do this at your own risk! These are the master switches
    207  * [SETTING] Privacy & Security>Security>... Block dangerous and deceptive content ***/
    208    // user_pref("browser.safebrowsing.malware.enabled", false);
    209    // user_pref("browser.safebrowsing.phishing.enabled", false);
    210 /* 0402: disable SB checks for downloads (both local lookups + remote)
    211  * This is the master switch for the safebrowsing.downloads* prefs (0403, 0404)
    212  * [SETTING] Privacy & Security>Security>... "Block dangerous downloads" ***/
    213    // user_pref("browser.safebrowsing.downloads.enabled", false);
    214 /* 0403: disable SB checks for downloads (remote)
    215  * To verify the safety of certain executable files, Firefox may submit some information about the
    216  * file, including the name, origin, size and a cryptographic hash of the contents, to the Google
    217  * Safe Browsing service which helps Firefox determine whether or not the file should be blocked
    218  * [SETUP-SECURITY] If you do not understand this, or you want this protection, then override this ***/
    219 user_pref("browser.safebrowsing.downloads.remote.enabled", false);
    220    // user_pref("browser.safebrowsing.downloads.remote.url", ""); // Defense-in-depth
    221 /* 0404: disable SB checks for unwanted software
    222  * [SETTING] Privacy & Security>Security>... "Warn you about unwanted and uncommon software" ***/
    223    // user_pref("browser.safebrowsing.downloads.remote.block_potentially_unwanted", false);
    224    // user_pref("browser.safebrowsing.downloads.remote.block_uncommon", false);
    225 /* 0405: disable "ignore this warning" on SB warnings [FF45+]
    226  * If clicked, it bypasses the block for that session. This is a means for admins to enforce SB
    227  * [TEST] see https://github.com/arkenfox/user.js/wiki/Appendix-A-Test-Sites#-mozilla
    228  * [1] https://bugzilla.mozilla.org/1226490 ***/
    229    // user_pref("browser.safebrowsing.allowOverride", false);
    230 
    231 /*** [SECTION 0600]: BLOCK IMPLICIT OUTBOUND [not explicitly asked for - e.g. clicked on] ***/
    232 user_pref("_user.js.parrot", "0600 syntax error: the parrot's no more!");
    233 /* 0601: disable link prefetching
    234  * [1] https://developer.mozilla.org/docs/Web/HTTP/Link_prefetching_FAQ ***/
    235 user_pref("network.prefetch-next", false);
    236 /* 0602: disable DNS prefetching
    237  * [1] https://developer.mozilla.org/docs/Web/HTTP/Headers/X-DNS-Prefetch-Control ***/
    238 user_pref("network.dns.disablePrefetch", true);
    239    // user_pref("network.dns.disablePrefetchFromHTTPS", true); // [DEFAULT: true]
    240 /* 0603: disable predictor / prefetching ***/
    241 user_pref("network.predictor.enabled", false);
    242 user_pref("network.predictor.enable-prefetch", false); // [FF48+] [DEFAULT: false]
    243 /* 0604: disable link-mouseover opening connection to linked server
    244  * [1] https://news.slashdot.org/story/15/08/14/2321202/how-to-quash-firefoxs-silent-requests ***/
    245 user_pref("network.http.speculative-parallel-limit", 0);
    246 /* 0605: disable mousedown speculative connections on bookmarks and history [FF98+] ***/
    247 user_pref("browser.places.speculativeConnect.enabled", false);
    248 /* 0610: enforce no "Hyperlink Auditing" (click tracking)
    249  * [1] https://www.bleepingcomputer.com/news/software/major-browsers-to-prevent-disabling-of-click-tracking-privacy-risk/ ***/
    250    // user_pref("browser.send_pings", false); // [DEFAULT: false]
    251 
    252 /*** [SECTION 0700]: DNS / DoH / PROXY / SOCKS ***/
    253 user_pref("_user.js.parrot", "0700 syntax error: the parrot's given up the ghost!");
    254 /* 0702: set the proxy server to do any DNS lookups when using SOCKS
    255  * e.g. in Tor, this stops your local DNS server from knowing your Tor destination
    256  * as a remote Tor node will handle the DNS request
    257  * [1] https://trac.torproject.org/projects/tor/wiki/doc/TorifyHOWTO/WebBrowsers ***/
    258 user_pref("network.proxy.socks_remote_dns", true);
    259 /* 0703: disable using UNC (Uniform Naming Convention) paths [FF61+]
    260  * [SETUP-CHROME] Can break extensions for profiles on network shares
    261  * [1] https://bugzilla.mozilla.org/1413868 ***/
    262 user_pref("network.file.disable_unc_paths", true); // [HIDDEN PREF]
    263 /* 0704: disable GIO as a potential proxy bypass vector
    264  * Gvfs/GIO has a set of supported protocols like obex, network, archive, computer,
    265  * dav, cdda, gphoto2, trash, etc. From FF87-117, by default only sftp was accepted
    266  * [1] https://bugzilla.mozilla.org/1433507
    267  * [2] https://en.wikipedia.org/wiki/GVfs
    268  * [3] https://en.wikipedia.org/wiki/GIO_(software) ***/
    269 user_pref("network.gio.supported-protocols", ""); // [HIDDEN PREF] [DEFAULT: "" FF118+]
    270 /* 0705: disable proxy direct failover for system requests [FF91+]
    271  * [WARNING] Default true is a security feature against malicious extensions [1]
    272  * [SETUP-CHROME] If you use a proxy and you trust your extensions
    273  * [1] https://blog.mozilla.org/security/2021/10/25/securing-the-proxy-api-for-firefox-add-ons/ ***/
    274    // user_pref("network.proxy.failover_direct", false);
    275 /* 0706: disable proxy bypass for system request failures [FF95+]
    276  * RemoteSettings, UpdateService, Telemetry [1]
    277  * [WARNING] If false, this will break the fallback for some security features
    278  * [SETUP-CHROME] If you use a proxy and you understand the security impact
    279  * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=1732792,1733994,1733481 ***/
    280    // user_pref("network.proxy.allow_bypass", false);
    281 /* 0710: enable DNS-over-HTTPS (DoH) [FF60+]
    282  * 0=default, 2=increased (TRR (Trusted Recursive Resolver) first), 3=max (TRR only), 5=off (no rollout)
    283  * see "doh-rollout.home-region": USA 2019, Canada 2021, Russia/Ukraine 2022 [3]
    284  * [SETTING] Privacy & Security>DNS over HTTPS
    285  * [1] https://hacks.mozilla.org/2018/05/a-cartoon-intro-to-dns-over-https/
    286  * [2] https://wiki.mozilla.org/Security/DOH-resolver-policy
    287  * [3] https://support.mozilla.org/en-US/kb/firefox-dns-over-https
    288  * [4] https://www.eff.org/deeplinks/2020/12/dns-doh-and-odoh-oh-my-year-review-2020 ***/
    289    // user_pref("network.trr.mode", 3);
    290 /* 0712: set DoH provider
    291  * The custom uri is the value shown when you "Choose provider>Custom>"
    292  * [NOTE] If you USE custom then "network.trr.uri" should be set the same
    293  * [SETTING] Privacy & Security>DNS over HTTPS>Increased/Max>Choose provider ***/
    294    // user_pref("network.trr.uri", "https://example.dns");
    295    // user_pref("network.trr.custom_uri", "https://example.dns");
    296 
    297 /*** [SECTION 0800]: LOCATION BAR / SEARCH BAR / SUGGESTIONS / HISTORY / FORMS ***/
    298 user_pref("_user.js.parrot", "0800 syntax error: the parrot's ceased to be!");
    299 /* 0801: disable location bar making speculative connections [FF56+]
    300  * [1] https://bugzilla.mozilla.org/1348275 ***/
    301 user_pref("browser.urlbar.speculativeConnect.enabled", false);
    302 /* 0802: disable location bar contextual suggestions
    303  * [NOTE] The UI is controlled by the .enabled pref
    304  * [SETTING] Search>Address Bar>Suggestions from...
    305  * [1] https://blog.mozilla.org/data/2021/09/15/data-and-firefox-suggest/ ***/
    306    // user_pref("browser.urlbar.quicksuggest.enabled", false); // [FF92+] [DEFAULT: false]
    307    // user_pref("browser.urlbar.suggest.quicksuggest.nonsponsored", false); // [FF95+] [DEFAULT: false]
    308    // user_pref("browser.urlbar.suggest.quicksuggest.sponsored", false); // [FF92+] [DEFAULT: false]
    309 /* 0803: disable live search suggestions
    310  * [NOTE] Both must be true for live search to work in the location bar
    311  * [SETUP-CHROME] Override these if you trust and use a privacy respecting search engine
    312  * [SETTING] Search>Provide search suggestions | Show search suggestions in address bar results ***/
    313 user_pref("browser.search.suggest.enabled", false);
    314 user_pref("browser.urlbar.suggest.searches", false);
    315 /* 0805: disable urlbar trending search suggestions [FF118+]
    316  * [SETTING] Search>Search Suggestions>Show trending search suggestions (FF119) ***/
    317 user_pref("browser.urlbar.trending.featureGate", false);
    318 /* 0806: disable urlbar suggestions ***/
    319 user_pref("browser.urlbar.addons.featureGate", false); // [FF115+]
    320 user_pref("browser.urlbar.mdn.featureGate", false); // [FF117+] [HIDDEN PREF]
    321 user_pref("browser.urlbar.pocket.featureGate", false); // [FF116+] [DEFAULT: false]
    322 user_pref("browser.urlbar.weather.featureGate", false); // [FF108+] [DEFAULT: false]
    323 user_pref("browser.urlbar.yelp.featureGate", false); // [FF124+] [DEFAULT: false]
    324 /* 0807: disable urlbar clipboard suggestions [FF118+] ***/
    325    // user_pref("browser.urlbar.clipboard.featureGate", false);
    326 /* 0810: disable search and form history
    327  * [SETUP-WEB] Be aware that autocomplete form data can be read by third parties [1][2]
    328  * [NOTE] We also clear formdata on exit (2811)
    329  * [SETTING] Privacy & Security>History>Custom Settings>Remember search and form history
    330  * [1] https://blog.mindedsecurity.com/2011/10/autocompleteagain.html
    331  * [2] https://bugzilla.mozilla.org/381681 ***/
    332 user_pref("browser.formfill.enable", false);
    333 /* 0815: disable tab-to-search [FF85+]
    334  * Alternatively, you can exclude on a per-engine basis by unchecking them in Options>Search
    335  * [SETTING] Search>Address Bar>When using the address bar, suggest>Search engines ***/
    336    // user_pref("browser.urlbar.suggest.engines", false);
    337 /* 0820: disable coloring of visited links
    338  * [SETUP-HARDEN] Bulk rapid history sniffing was mitigated in 2010 [1][2]. Slower and more expensive
    339  * redraw timing attacks were largely mitigated in FF77+ [3]. Using RFP (4501) further hampers timing
    340  * attacks. Don't forget clearing history on exit (2811). However, social engineering [2#limits][4][5]
    341  * and advanced targeted timing attacks could still produce usable results
    342  * [1] https://developer.mozilla.org/docs/Web/CSS/Privacy_and_the_:visited_selector
    343  * [2] https://dbaron.org/mozilla/visited-privacy
    344  * [3] https://bugzilla.mozilla.org/1632765
    345  * [4] https://earthlng.github.io/testpages/visited_links.html (see github wiki APPENDIX A on how to use)
    346  * [5] https://lcamtuf.blogspot.com/2016/08/css-mix-blend-mode-is-bad-for-keeping.html ***/
    347    // user_pref("layout.css.visited_links_enabled", false);
    348 /* 0830: enable separate default search engine in Private Windows and its UI setting
    349  * [SETTING] Search>Default Search Engine>Choose a different default search engine for Private Windows only ***/
    350 user_pref("browser.search.separatePrivateDefault", true); // [FF70+]
    351 user_pref("browser.search.separatePrivateDefault.ui.enabled", true); // [FF71+]
    352 
    353 /*** [SECTION 0900]: PASSWORDS
    354    [1] https://support.mozilla.org/kb/use-primary-password-protect-stored-logins-and-pas
    355 ***/
    356 user_pref("_user.js.parrot", "0900 syntax error: the parrot's expired!");
    357 /* 0903: disable auto-filling username & password form fields
    358  * can leak in cross-site forms *and* be spoofed
    359  * [NOTE] Username & password is still available when you enter the field
    360  * [SETTING] Privacy & Security>Logins and Passwords>Autofill logins and passwords
    361  * [1] https://freedom-to-tinker.com/2017/12/27/no-boundaries-for-user-identities-web-trackers-exploit-browser-login-managers/
    362  * [2] https://homes.esat.kuleuven.be/~asenol/leaky-forms/ ***/
    363 user_pref("signon.autofillForms", false);
    364 /* 0904: disable formless login capture for Password Manager [FF51+] ***/
    365 user_pref("signon.formlessCapture.enabled", false);
    366 /* 0905: limit (or disable) HTTP authentication credentials dialogs triggered by sub-resources [FF41+]
    367  * hardens against potential credentials phishing
    368  * 0 = don't allow sub-resources to open HTTP authentication credentials dialogs
    369  * 1 = don't allow cross-origin sub-resources to open HTTP authentication credentials dialogs
    370  * 2 = allow sub-resources to open HTTP authentication credentials dialogs (default) ***/
    371 user_pref("network.auth.subresource-http-auth-allow", 1);
    372 /* 0906: enforce no automatic authentication on Microsoft sites [FF91+] [WINDOWS 10+]
    373  * [SETTING] Privacy & Security>Logins and Passwords>Allow Windows single sign-on for...
    374  * [1] https://support.mozilla.org/kb/windows-sso ***/
    375    // user_pref("network.http.windows-sso.enabled", false); // [DEFAULT: false]
    376 
    377 /*** [SECTION 1000]: DISK AVOIDANCE ***/
    378 user_pref("_user.js.parrot", "1000 syntax error: the parrot's gone to meet 'is maker!");
    379 /* 1001: disable disk cache
    380  * [SETUP-CHROME] If you think disk cache helps perf, then feel free to override this
    381  * [NOTE] We also clear cache on exit (2811) ***/
    382 user_pref("browser.cache.disk.enable", false);
    383 /* 1002: disable media cache from writing to disk in Private Browsing
    384  * [NOTE] MSE (Media Source Extensions) are already stored in-memory in PB ***/
    385 user_pref("browser.privatebrowsing.forceMediaMemoryCache", true); // [FF75+]
    386 user_pref("media.memory_cache_max_size", 65536);
    387 /* 1003: disable storing extra session data [SETUP-CHROME]
    388  * define on which sites to save extra session data such as form content, cookies and POST data
    389  * 0=everywhere, 1=unencrypted sites, 2=nowhere ***/
    390 user_pref("browser.sessionstore.privacy_level", 2);
    391 /* 1005: disable automatic Firefox start and session restore after reboot [FF62+] [WINDOWS]
    392  * [1] https://bugzilla.mozilla.org/603903 ***/
    393 user_pref("toolkit.winRegisterApplicationRestart", false);
    394 /* 1006: disable favicons in shortcuts [WINDOWS]
    395  * URL shortcuts use a cached randomly named .ico file which is stored in your
    396  * profile/shortcutCache directory. The .ico remains after the shortcut is deleted
    397  * If set to false then the shortcuts use a generic Firefox icon ***/
    398 user_pref("browser.shell.shortcutFavicons", false);
    399 
    400 /*** [SECTION 1200]: HTTPS (SSL/TLS / OCSP / CERTS / HPKP)
    401    Your cipher and other settings can be used in server side fingerprinting
    402    [TEST] https://www.ssllabs.com/ssltest/viewMyClient.html
    403    [TEST] https://browserleaks.com/ssl
    404    [TEST] https://ja3er.com/
    405    [1] https://www.securityartwork.es/2017/02/02/tls-client-fingerprinting-with-bro/
    406 ***/
    407 user_pref("_user.js.parrot", "1200 syntax error: the parrot's a stiff!");
    408 /** SSL (Secure Sockets Layer) / TLS (Transport Layer Security) ***/
    409 /* 1201: require safe negotiation
    410  * Blocks connections to servers that don't support RFC 5746 [2] as they're potentially vulnerable to a
    411  * MiTM attack [3]. A server without RFC 5746 can be safe from the attack if it disables renegotiations
    412  * but the problem is that the browser can't know that. Setting this pref to true is the only way for the
    413  * browser to ensure there will be no unsafe renegotiations on the channel between the browser and the server
    414  * [SETUP-WEB] SSL_ERROR_UNSAFE_NEGOTIATION: is it worth overriding this for that one site?
    415  * [STATS] SSL Labs (May 2024) reports over 99.7% of top sites have secure renegotiation [4]
    416  * [1] https://wiki.mozilla.org/Security:Renegotiation
    417  * [2] https://datatracker.ietf.org/doc/html/rfc5746
    418  * [3] https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-3555
    419  * [4] https://www.ssllabs.com/ssl-pulse/ ***/
    420 user_pref("security.ssl.require_safe_negotiation", true);
    421 /* 1206: disable TLS1.3 0-RTT (round-trip time) [FF51+]
    422  * This data is not forward secret, as it is encrypted solely under keys derived using
    423  * the offered PSK. There are no guarantees of non-replay between connections
    424  * [1] https://github.com/tlswg/tls13-spec/issues/1001
    425  * [2] https://www.rfc-editor.org/rfc/rfc9001.html#name-replay-attacks-with-0-rtt
    426  * [3] https://blog.cloudflare.com/tls-1-3-overview-and-q-and-a/ ***/
    427 user_pref("security.tls.enable_0rtt_data", false);
    428 
    429 /** OCSP (Online Certificate Status Protocol)
    430    [1] https://scotthelme.co.uk/revocation-is-broken/
    431    [2] https://blog.mozilla.org/security/2013/07/29/ocsp-stapling-in-firefox/
    432 ***/
    433 /* 1211: enforce OCSP fetching to confirm current validity of certificates
    434  * 0=disabled, 1=enabled (default), 2=enabled for EV certificates only
    435  * OCSP (non-stapled) leaks information about the sites you visit to the CA (cert authority)
    436  * It's a trade-off between security (checking) and privacy (leaking info to the CA)
    437  * [NOTE] This pref only controls OCSP fetching and does not affect OCSP stapling
    438  * [SETTING] Privacy & Security>Security>Certificates>Query OCSP responder servers...
    439  * [1] https://en.wikipedia.org/wiki/Ocsp ***/
    440 user_pref("security.OCSP.enabled", 1); // [DEFAULT: 1]
    441 /* 1212: set OCSP fetch failures (non-stapled, see 1211) to hard-fail
    442  * [SETUP-WEB] SEC_ERROR_OCSP_SERVER_ERROR
    443  * When a CA cannot be reached to validate a cert, Firefox just continues the connection (=soft-fail)
    444  * Setting this pref to true tells Firefox to instead terminate the connection (=hard-fail)
    445  * It is pointless to soft-fail when an OCSP fetch fails: you cannot confirm a cert is still valid (it
    446  * could have been revoked) and/or you could be under attack (e.g. malicious blocking of OCSP servers)
    447  * [1] https://blog.mozilla.org/security/2013/07/29/ocsp-stapling-in-firefox/
    448  * [2] https://www.imperialviolet.org/2014/04/19/revchecking.html ***/
    449 user_pref("security.OCSP.require", true);
    450 
    451 /** CERTS / HPKP (HTTP Public Key Pinning) ***/
    452 /* 1223: enable strict PKP (Public Key Pinning)
    453  * 0=disabled, 1=allow user MiTM (default; such as your antivirus), 2=strict
    454  * [SETUP-WEB] MOZILLA_PKIX_ERROR_KEY_PINNING_FAILURE ***/
    455 user_pref("security.cert_pinning.enforcement_level", 2);
    456 /* 1224: enable CRLite [FF73+]
    457  * 0 = disabled
    458  * 1 = consult CRLite but only collect telemetry
    459  * 2 = consult CRLite and enforce both "Revoked" and "Not Revoked" results
    460  * 3 = consult CRLite and enforce "Not Revoked" results, but defer to OCSP for "Revoked" (default)
    461  * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=1429800,1670985,1753071
    462  * [2] https://blog.mozilla.org/security/tag/crlite/ ***/
    463 user_pref("security.remote_settings.crlite_filters.enabled", true);
    464 user_pref("security.pki.crlite_mode", 2);
    465 
    466 /** MIXED CONTENT ***/
    467 /* 1241: disable insecure passive content (such as images) on https pages ***/
    468    // user_pref("security.mixed_content.block_display_content", true); // Defense-in-depth (see 1244)
    469 /* 1244: enable HTTPS-Only mode in all windows
    470  * When the top-level is HTTPS, insecure subresources are also upgraded (silent fail)
    471  * [SETTING] to add site exceptions: Padlock>HTTPS-Only mode>On (after "Continue to HTTP Site")
    472  * [SETTING] Privacy & Security>HTTPS-Only Mode (and manage exceptions)
    473  * [TEST] http://example.com [upgrade]
    474  * [TEST] http://httpforever.com/ | http://http.rip [no upgrade] ***/
    475 user_pref("dom.security.https_only_mode", true); // [FF76+]
    476    // user_pref("dom.security.https_only_mode_pbm", true); // [FF80+]
    477 /* 1245: enable HTTPS-Only mode for local resources [FF77+] ***/
    478    // user_pref("dom.security.https_only_mode.upgrade_local", true);
    479 /* 1246: disable HTTP background requests [FF82+]
    480  * When attempting to upgrade, if the server doesn't respond within 3 seconds, Firefox sends
    481  * a top-level HTTP request without path in order to check if the server supports HTTPS or not
    482  * This is done to avoid waiting for a timeout which takes 90 seconds
    483  * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=1642387,1660945 ***/
    484 user_pref("dom.security.https_only_mode_send_http_background_request", false);
    485 
    486 /** UI (User Interface) ***/
    487 /* 1270: display warning on the padlock for "broken security" (if 1201 is false)
    488  * Bug: warning padlock not indicated for subresources on a secure page! [2]
    489  * [1] https://wiki.mozilla.org/Security:Renegotiation
    490  * [2] https://bugzilla.mozilla.org/1353705 ***/
    491 user_pref("security.ssl.treat_unsafe_negotiation_as_broken", true);
    492 /* 1272: display advanced information on Insecure Connection warning pages
    493  * only works when it's possible to add an exception
    494  * i.e. it doesn't work for HSTS discrepancies (https://subdomain.preloaded-hsts.badssl.com/)
    495  * [TEST] https://expired.badssl.com/ ***/
    496 user_pref("browser.xul.error_pages.expert_bad_cert", true);
    497 
    498 /*** [SECTION 1600]: REFERERS
    499                   full URI: https://example.com:8888/foo/bar.html?id=1234
    500      scheme+host+port+path: https://example.com:8888/foo/bar.html
    501           scheme+host+port: https://example.com:8888
    502    [1] https://feeding.cloud.geek.nz/posts/tweaking-referrer-for-privacy-in-firefox/
    503 ***/
    504 user_pref("_user.js.parrot", "1600 syntax error: the parrot rests in peace!");
    505 /* 1602: control the amount of cross-origin information to send [FF52+]
    506  * 0=send full URI (default), 1=scheme+host+port+path, 2=scheme+host+port ***/
    507 user_pref("network.http.referer.XOriginTrimmingPolicy", 2);
    508 
    509 /*** [SECTION 1700]: CONTAINERS ***/
    510 user_pref("_user.js.parrot", "1700 syntax error: the parrot's bit the dust!");
    511 /* 1701: enable Container Tabs and its UI setting [FF50+]
    512  * [SETTING] General>Tabs>Enable Container Tabs
    513  * https://wiki.mozilla.org/Security/Contextual_Identity_Project/Containers ***/
    514 user_pref("privacy.userContext.enabled", true);
    515 user_pref("privacy.userContext.ui.enabled", true);
    516 /* 1702: set behavior on "+ Tab" button to display container menu on left click [FF74+]
    517  * [NOTE] The menu is always shown on long press and right click
    518  * [SETTING] General>Tabs>Enable Container Tabs>Settings>Select a container for each new tab ***/
    519    // user_pref("privacy.userContext.newTabContainerOnLeftClick.enabled", true);
    520 /* 1703: set external links to open in site-specific containers [FF123+]
    521  * [SETUP-WEB] Depending on your container extension(s) and their settings
    522  * true=Firefox will not choose a container (so your extension can)
    523  * false=Firefox will choose the container/no-container (default)
    524  * [1] https://bugzilla.mozilla.org/1874599 ***/
    525    // user_pref("browser.link.force_default_user_context_id_for_external_opens", true);
    526 
    527 /*** [SECTION 2000]: PLUGINS / MEDIA / WEBRTC ***/
    528 user_pref("_user.js.parrot", "2000 syntax error: the parrot's snuffed it!");
    529 /* 2002: force WebRTC inside the proxy [FF70+] ***/
    530 user_pref("media.peerconnection.ice.proxy_only_if_behind_proxy", true);
    531 /* 2003: force a single network interface for ICE candidates generation [FF42+]
    532  * When using a system-wide proxy, it uses the proxy interface
    533  * [1] https://developer.mozilla.org/en-US/docs/Web/API/RTCIceCandidate
    534  * [2] https://wiki.mozilla.org/Media/WebRTC/Privacy ***/
    535 user_pref("media.peerconnection.ice.default_address_only", true);
    536 /* 2004: force exclusion of private IPs from ICE candidates [FF51+]
    537  * [SETUP-HARDEN] This will protect your private IP even in TRUSTED scenarios after you
    538  * grant device access, but often results in breakage on video-conferencing platforms ***/
    539    // user_pref("media.peerconnection.ice.no_host", true);
    540 /* 2020: disable GMP (Gecko Media Plugins)
    541  * [1] https://wiki.mozilla.org/GeckoMediaPlugins ***/
    542    // user_pref("media.gmp-provider.enabled", false);
    543 
    544 /*** [SECTION 2400]: DOM (DOCUMENT OBJECT MODEL) ***/
    545 user_pref("_user.js.parrot", "2400 syntax error: the parrot's kicked the bucket!");
    546 /* 2402: prevent scripts from moving and resizing open windows ***/
    547 user_pref("dom.disable_window_move_resize", true);
    548 
    549 /*** [SECTION 2600]: MISCELLANEOUS ***/
    550 user_pref("_user.js.parrot", "2600 syntax error: the parrot's run down the curtain!");
    551 /* 2603: remove temp files opened from non-PB windows with an external application
    552  * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=302433,1738574 ***/
    553 user_pref("browser.download.start_downloads_in_tmp_dir", true); // [FF102+]
    554 user_pref("browser.helperApps.deleteTempFileOnExit", true);
    555 /* 2606: disable UITour backend so there is no chance that a remote page can use it ***/
    556 user_pref("browser.uitour.enabled", false);
    557    // user_pref("browser.uitour.url", ""); // Defense-in-depth
    558 /* 2608: reset remote debugging to disabled
    559  * [1] https://gitlab.torproject.org/tpo/applications/tor-browser/-/issues/16222 ***/
    560 user_pref("devtools.debugger.remote-enabled", false); // [DEFAULT: false]
    561 /* 2615: disable websites overriding Firefox's keyboard shortcuts [FF58+]
    562  * 0 (default) or 1=allow, 2=block
    563  * [SETTING] to add site exceptions: Ctrl+I>Permissions>Override Keyboard Shortcuts ***/
    564    // user_pref("permissions.default.shortcuts", 2);
    565 /* 2616: remove special permissions for certain mozilla domains [FF35+]
    566  * [1] resource://app/defaults/permissions ***/
    567 user_pref("permissions.manager.defaultsUrl", "");
    568 /* 2617: remove webchannel whitelist ***/
    569 user_pref("webchannel.allowObject.urlWhitelist", "");
    570 /* 2619: use Punycode in Internationalized Domain Names to eliminate possible spoofing
    571  * [SETUP-WEB] Might be undesirable for non-latin alphabet users since legitimate IDN's are also punycoded
    572  * [TEST] https://www.xn--80ak6aa92e.com/ (www.apple.com)
    573  * [1] https://wiki.mozilla.org/IDN_Display_Algorithm
    574  * [2] https://en.wikipedia.org/wiki/IDN_homograph_attack
    575  * [3] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=punycode+firefox
    576  * [4] https://www.xudongz.com/blog/2017/idn-phishing/ ***/
    577 user_pref("network.IDN_show_punycode", true);
    578 /* 2620: enforce PDFJS, disable PDFJS scripting
    579  * This setting controls if the option "Display in Firefox" is available in the setting below
    580  *   and by effect controls whether PDFs are handled in-browser or externally ("Ask" or "Open With")
    581  * [WHY] pdfjs is lightweight, open source, and secure: the last exploit was June 2015 [1]
    582  *   It doesn't break "state separation" of browser content (by not sharing with OS, independent apps).
    583  *   It maintains disk avoidance and application data isolation. It's convenient. You can still save to disk.
    584  * [NOTE] JS can still force a pdf to open in-browser by bundling its own code
    585  * [SETUP-CHROME] You may prefer a different pdf reader for security/workflow reasons
    586  * [SETTING] General>Applications>Portable Document Format (PDF)
    587  * [1] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=pdf.js+firefox ***/
    588 user_pref("pdfjs.disabled", false); // [DEFAULT: false]
    589 user_pref("pdfjs.enableScripting", false); // [FF86+]
    590 /* 2624: disable middle click on new tab button opening URLs or searches using clipboard [FF115+] */
    591 user_pref("browser.tabs.searchclipboardfor.middleclick", false); // [DEFAULT: false NON-LINUX]
    592 /* 2630: disable content analysis by DLP (Data Loss Prevention) agents
    593  * DLP agents are background processes on managed computers that allow enterprises to monitor locally running
    594  * applications for data exfiltration events, which they can allow/block based on customer defined DLP policies.
    595  * [1] https://github.com/chromium/content_analysis_sdk */
    596 user_pref("browser.contentanalysis.default_allow", false); // [FF124+] [DEFAULT: false]
    597 
    598 /** DOWNLOADS ***/
    599 /* 2651: enable user interaction for security by always asking where to download
    600  * [SETUP-CHROME] On Android this blocks longtapping and saving images
    601  * [SETTING] General>Downloads>Always ask you where to save files ***/
    602 user_pref("browser.download.useDownloadDir", false);
    603 /* 2652: disable downloads panel opening on every download [FF96+] ***/
    604 user_pref("browser.download.alwaysOpenPanel", false);
    605 /* 2653: disable adding downloads to the system's "recent documents" list ***/
    606 user_pref("browser.download.manager.addToRecentDocs", false);
    607 /* 2654: enable user interaction for security by always asking how to handle new mimetypes [FF101+]
    608  * [SETTING] General>Files and Applications>What should Firefox do with other files ***/
    609 user_pref("browser.download.always_ask_before_handling_new_types", true);
    610 
    611 /** EXTENSIONS ***/
    612 /* 2660: limit allowed extension directories
    613  * 1=profile, 2=user, 4=application, 8=system, 16=temporary, 31=all
    614  * The pref value represents the sum: e.g. 5 would be profile and application directories
    615  * [SETUP-CHROME] Breaks usage of files which are installed outside allowed directories
    616  * [1] https://archive.is/DYjAM ***/
    617 user_pref("extensions.enabledScopes", 5); // [HIDDEN PREF]
    618    // user_pref("extensions.autoDisableScopes", 15); // [DEFAULT: 15]
    619 /* 2661: disable bypassing 3rd party extension install prompts [FF82+]
    620  * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=1659530,1681331 ***/
    621 user_pref("extensions.postDownloadThirdPartyPrompt", false);
    622 /* 2662: disable webextension restrictions on certain mozilla domains (you also need 4503) [FF60+]
    623  * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=1384330,1406795,1415644,1453988 ***/
    624    // user_pref("extensions.webextensions.restrictedDomains", "");
    625 
    626 /*** [SECTION 2700]: ETP (ENHANCED TRACKING PROTECTION) ***/
    627 user_pref("_user.js.parrot", "2700 syntax error: the parrot's joined the bleedin' choir invisible!");
    628 /* 2701: enable ETP Strict Mode [FF86+]
    629  * ETP Strict Mode enables Total Cookie Protection (TCP)
    630  * [NOTE] Adding site exceptions disables all ETP protections for that site and increases the risk of
    631  * cross-site state tracking e.g. exceptions for SiteA and SiteB means PartyC on both sites is shared
    632  * [1] https://blog.mozilla.org/security/2021/02/23/total-cookie-protection/
    633  * [SETTING] to add site exceptions: Urlbar>ETP Shield
    634  * [SETTING] to manage site exceptions: Options>Privacy & Security>Enhanced Tracking Protection>Manage Exceptions ***/
    635 user_pref("browser.contentblocking.category", "strict"); // [HIDDEN PREF]
    636 /* 2702: disable ETP web compat features [FF93+]
    637  * [SETUP-HARDEN] Includes skip lists, heuristics (SmartBlock) and automatic grants
    638  * Opener and redirect heuristics are granted for 30 days, see [3]
    639  * [1] https://blog.mozilla.org/security/2021/07/13/smartblock-v2/
    640  * [2] https://hg.mozilla.org/mozilla-central/rev/e5483fd469ab#l4.12
    641  * [3] https://developer.mozilla.org/en-US/docs/Web/Privacy/State_Partitioning#storage_access_heuristics ***/
    642    // user_pref("privacy.antitracking.enableWebcompat", false);
    643 
    644 /*** [SECTION 2800]: SHUTDOWN & SANITIZING ***/
    645 user_pref("_user.js.parrot", "2800 syntax error: the parrot's bleedin' demised!");
    646 /* 2810: enable Firefox to clear items on shutdown
    647  * [SETTING] Privacy & Security>History>Custom Settings>Clear history when Firefox closes | Settings ***/
    648 user_pref("privacy.sanitize.sanitizeOnShutdown", true);
    649 
    650 /** SANITIZE ON SHUTDOWN: IGNORES "ALLOW" SITE EXCEPTIONS | v2 migration is FF128+ ***/
    651 /* 2811: set/enforce what items to clear on shutdown (if 2810 is true) [SETUP-CHROME]
    652  * [NOTE] If "history" is true, downloads will also be cleared ***/
    653 user_pref("privacy.clearOnShutdown.cache", true);     // [DEFAULT: true]
    654 user_pref("privacy.clearOnShutdown_v2.cache", true);  // [FF128+] [DEFAULT: true]
    655 user_pref("privacy.clearOnShutdown.downloads", true); // [DEFAULT: true]
    656 user_pref("privacy.clearOnShutdown.formdata", true);  // [DEFAULT: true]
    657 user_pref("privacy.clearOnShutdown.history", true);   // [DEFAULT: true]
    658 user_pref("privacy.clearOnShutdown_v2.historyFormDataAndDownloads", true); // [FF128+] [DEFAULT: true]
    659    // user_pref("privacy.clearOnShutdown.siteSettings", false); // [DEFAULT: false]
    660    // user_pref("privacy.clearOnShutdown_v2.siteSettings", false); // [FF128+] [DEFAULT: false]
    661 /* 2812: set Session Restore to clear on shutdown (if 2810 is true) [FF34+]
    662  * [NOTE] Not needed if Session Restore is not used (0102) or it is already cleared with history (2811)
    663  * [NOTE] If true, this prevents resuming from crashes (also see 5008) ***/
    664    // user_pref("privacy.clearOnShutdown.openWindows", true);
    665 
    666 /** SANITIZE ON SHUTDOWN: RESPECTS "ALLOW" SITE EXCEPTIONS FF103+ | v2 migration is FF128+ ***/
    667 /* 2815: set "Cookies" and "Site Data" to clear on shutdown (if 2810 is true) [SETUP-CHROME]
    668  * [NOTE] Exceptions: A "cookie" block permission also controls "offlineApps" (see note below).
    669  * serviceWorkers require an "Allow" permission. For cross-domain logins, add exceptions for
    670  * both sites e.g. https://www.youtube.com (site) + https://accounts.google.com (single sign on)
    671  * [NOTE] "offlineApps": Offline Website Data: localStorage, service worker cache, QuotaManager (IndexedDB, asm-cache)
    672  * [NOTE] "sessions": Active Logins (has no site exceptions): refers to HTTP Basic Authentication [1], not logins via cookies
    673  * [WARNING] Be selective with what sites you "Allow", as they also disable partitioning (1767271)
    674  * [SETTING] to add site exceptions: Ctrl+I>Permissions>Cookies>Allow (when on the website in question)
    675  * [SETTING] to manage site exceptions: Options>Privacy & Security>Permissions>Settings
    676  * [1] https://en.wikipedia.org/wiki/Basic_access_authentication ***/
    677 user_pref("privacy.clearOnShutdown.cookies", true); // Cookies
    678 user_pref("privacy.clearOnShutdown.offlineApps", true); // Site Data
    679 user_pref("privacy.clearOnShutdown.sessions", true);  // Active Logins [DEFAULT: true]
    680 user_pref("privacy.clearOnShutdown_v2.cookiesAndStorage", true); // Cookies, Site Data, Active Logins [FF128+]
    681 
    682 /** SANITIZE SITE DATA: IGNORES "ALLOW" SITE EXCEPTIONS ***/
    683 /* 2820: set manual "Clear Data" items [SETUP-CHROME] [FF128+]
    684  * Firefox remembers your last choices. This will reset them when you start Firefox
    685  * [SETTING] Privacy & Security>Browser Privacy>Cookies and Site Data>Clear Data ***/
    686 user_pref("privacy.clearSiteData.cache", true);
    687 user_pref("privacy.clearSiteData.cookiesAndStorage", false); // keep false until it respects "allow" site exceptions
    688 user_pref("privacy.clearSiteData.historyFormDataAndDownloads", true);
    689    // user_pref("privacy.clearSiteData.siteSettings", false);
    690 
    691 /** SANITIZE HISTORY: IGNORES "ALLOW" SITE EXCEPTIONS | clearHistory migration is FF128+ ***/
    692 /* 2830: set manual "Clear History" items, also via Ctrl-Shift-Del [SETUP-CHROME]
    693  * Firefox remembers your last choices. This will reset them when you start Firefox
    694  * [NOTE] Regardless of what you set "downloads" to, as soon as the dialog
    695  * for "Clear Recent History" is opened, it is synced to the same as "history"
    696  * [SETTING] Privacy & Security>History>Custom Settings>Clear History ***/
    697 user_pref("privacy.cpd.cache", true);    // [DEFAULT: true]
    698 user_pref("privacy.clearHistory.cache", true);
    699 user_pref("privacy.cpd.formdata", true); // [DEFAULT: true]
    700 user_pref("privacy.cpd.history", true);  // [DEFAULT: true]
    701    // user_pref("privacy.cpd.downloads", true); // not used, see note above
    702 user_pref("privacy.clearHistory.historyFormDataAndDownloads", true);
    703 user_pref("privacy.cpd.cookies", false);
    704 user_pref("privacy.cpd.sessions", true); // [DEFAULT: true]
    705 user_pref("privacy.cpd.offlineApps", false); // [DEFAULT: false]
    706 user_pref("privacy.clearHistory.cookiesAndStorage", false);
    707    // user_pref("privacy.cpd.openWindows", false); // Session Restore
    708    // user_pref("privacy.cpd.passwords", false);
    709    // user_pref("privacy.cpd.siteSettings", false);
    710    // user_pref("privacy.clearHistory.siteSettings", false);
    711 
    712 /** SANITIZE MANUAL: TIMERANGE ***/
    713 /* 2840: set "Time range to clear" for "Clear Data" (2820) and "Clear History" (2830)
    714  * Firefox remembers your last choice. This will reset the value when you start Firefox
    715  * 0=everything, 1=last hour, 2=last two hours, 3=last four hours, 4=today
    716  * [NOTE] Values 5 (last 5 minutes) and 6 (last 24 hours) are not listed in the dropdown,
    717  * which will display a blank value, and are not guaranteed to work ***/
    718 user_pref("privacy.sanitize.timeSpan", 0);
    719 
    720 /*** [SECTION 4000]: FPP (fingerprintingProtection)
    721    RFP (4501) overrides FPP
    722 
    723    In FF118+ FPP is on by default in private windows (4001) and in FF119+ is controlled
    724    by ETP (2701). FPP will also use Remote Services in future to relax FPP protections
    725    on a per site basis for compatibility (4003).
    726 
    727    1826408 - restrict fonts to system (kBaseFonts + kLangPackFonts) (Windows, Mac, some Linux)
    728       https://searchfox.org/mozilla-central/search?path=StandardFonts*.inc
    729    1858181 - subtly randomize canvas per eTLD+1, per session and per window-mode (FF120+)
    730 ***/
    731 user_pref("_user.js.parrot", "4000 syntax error: the parrot's bereft of life!");
    732 /* 4001: enable FPP in PB mode [FF114+]
    733  * [NOTE] In FF119+, FPP for all modes (7016) is enabled with ETP Strict (2701) ***/
    734    // user_pref("privacy.fingerprintingProtection.pbmode", true); // [DEFAULT: true FF118+]
    735 /* 4002: set global FPP overrides [FF114+]
    736  * Controls what protections FPP uses globally, including "RFPTargets" (despite the name these are
    737  * not used by RFP) e.g. "+AllTargets,-CSSPrefersColorScheme" or "-AllTargets,+CanvasRandomization"
    738  * [NOTE] Be aware that not all RFP protections are necessarily in RFPTargets
    739  * [WARNING] Not recommended. Either use RFP or FPP at defaults
    740  * [1] https://searchfox.org/mozilla-central/source/toolkit/components/resistfingerprinting/RFPTargets.inc ***/
    741    // user_pref("privacy.fingerprintingProtection.overrides", "");
    742 /* 4003: disable remote FPP overrides [FF127+] ***/
    743    // user_pref("privacy.fingerprintingProtection.remoteOverrides.enabled", false);
    744 
    745 /*** [SECTION 4500]: RFP (resistFingerprinting)
    746    RFP overrides FPP (4000)
    747 
    748    It is an all-or-nothing buy in: you cannot pick and choose what parts you want
    749    [TEST] https://arkenfox.github.io/TZP/tzp.html
    750 
    751    [WARNING] DO NOT USE extensions to alter RFP protected metrics
    752 
    753     418986 - limit window.screen & CSS media queries (FF41)
    754    1281949 - spoof screen orientation (FF50)
    755    1360039 - spoof navigator.hardwareConcurrency as 2 (FF55)
    756  FF56
    757    1333651 - spoof User Agent & Navigator API
    758       version: android version spoofed as ESR (FF119 or lower)
    759       OS: JS spoofed as Windows 10, OS 10.15, Android 10, or Linux | HTTP Headers spoofed as Windows or Android
    760    1369319 - disable device sensor API
    761    1369357 - disable site specific zoom
    762    1337161 - hide gamepads from content
    763    1372072 - spoof network information API as "unknown" when dom.netinfo.enabled = true
    764    1333641 - reduce fingerprinting in WebSpeech API
    765  FF57
    766    1369309 - spoof media statistics
    767    1382499 - reduce screen co-ordinate fingerprinting in Touch API
    768    1217290 & 1409677 - enable some fingerprinting resistance for WebGL
    769    1354633 - limit MediaError.message to a whitelist
    770  FF58+
    771    1372073 - spoof/block fingerprinting in MediaDevices API (FF59)
    772       Spoof: enumerate devices as one "Internal Camera" and one "Internal Microphone"
    773       Block: suppresses the ondevicechange event
    774    1039069 - warn when language prefs are not set to "en*" (FF59)
    775    1222285 & 1433592 - spoof keyboard events and suppress keyboard modifier events (FF59)
    776       Spoofing mimics the content language of the document. Currently it only supports en-US.
    777       Modifier events suppressed are SHIFT and both ALT keys. Chrome is not affected.
    778    1337157 - disable WebGL debug renderer info (FF60)
    779    1459089 - disable OS locale in HTTP Accept-Language headers (ANDROID) (FF62)
    780    1479239 - return "no-preference" with prefers-reduced-motion (FF63)
    781    1363508 - spoof/suppress Pointer Events (FF64)
    782    1492766 - spoof pointerEvent.pointerid (FF65)
    783    1485266 - disable exposure of system colors to CSS or canvas (FF67)
    784    1494034 - return "light" with prefers-color-scheme (FF67)
    785    1564422 - spoof audioContext outputLatency (FF70)
    786    1595823 - return audioContext sampleRate as 44100 (FF72)
    787    1607316 - spoof pointer as coarse and hover as none (ANDROID) (FF74)
    788    1621433 - randomize canvas (previously FF58+ returned an all-white canvas) (FF78)
    789    1506364 - return "no-preference" with prefers-contrast (FF80)
    790    1653987 - limit font visibility to bundled and "Base Fonts" (Windows, Mac, some Linux) (FF80)
    791    1461454 - spoof smooth=true and powerEfficient=false for supported media in MediaCapabilities (FF82)
    792     531915 - use fdlibm's sin, cos and tan in jsmath (FF93, ESR91.1)
    793    1756280 - enforce navigator.pdfViewerEnabled as true and plugins/mimeTypes as hard-coded values (FF100-115)
    794    1692609 - reduce JS timing precision to 16.67ms (previously FF55+ was 100ms) (FF102)
    795    1422237 - return "srgb" with color-gamut (FF110)
    796    1794628 - return "none" with inverted-colors (FF114)
    797    1554751 - return devicePixelRatio as 2 (previously FF41+ was 1) (FF127)
    798    1787790 - normalize system fonts (FF128)
    799    1835987 - spoof timezone as Atlantic/Reykjavik (previously FF55+ was UTC) (FF128)
    800 ***/
    801 user_pref("_user.js.parrot", "4500 syntax error: the parrot's popped 'is clogs");
    802 /* 4501: enable RFP
    803  * [SETUP-WEB] RFP can cause some website breakage: mainly canvas, use a canvas site exception via the urlbar.
    804  * RFP also has a few side effects: mainly timezone is UTC, and websites will prefer light theme
    805  * [NOTE] pbmode applies if true and the original pref is false
    806  * [1] https://bugzilla.mozilla.org/418986 ***/
    807 user_pref("privacy.resistFingerprinting", true); // [FF41+]
    808    // user_pref("privacy.resistFingerprinting.pbmode", true); // [FF114+]
    809 /* 4502: set new window size rounding max values [FF55+]
    810  * [SETUP-CHROME] sizes round down in hundreds: width to 200s and height to 100s, to fit your screen
    811  * [1] https://bugzilla.mozilla.org/1330882 ***/
    812 user_pref("privacy.window.maxInnerWidth", 1600);
    813 user_pref("privacy.window.maxInnerHeight", 900);
    814 /* 4503: disable mozAddonManager Web API [FF57+]
    815  * [NOTE] To allow extensions to work on AMO, you also need 2662
    816  * [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=1384330,1406795,1415644,1453988 ***/
    817 user_pref("privacy.resistFingerprinting.block_mozAddonManager", true);
    818 /* 4504: enable RFP letterboxing [FF67+]
    819  * Dynamically resizes the inner window by applying margins in stepped ranges [2]
    820  * If you use the dimension pref, then it will only apply those resolutions.
    821  * The format is "width1xheight1, width2xheight2, ..." (e.g. "800x600, 1000x1000")
    822  * [SETUP-WEB] This is independent of RFP (4501). If you're not using RFP, or you are but
    823  * dislike the margins, then flip this pref, keeping in mind that it is effectively fingerprintable
    824  * [WARNING] DO NOT USE: the dimension pref is only meant for testing
    825  * [1] https://bugzilla.mozilla.org/1407366
    826  * [2] https://hg.mozilla.org/mozilla-central/rev/6d2d7856e468#l2.32 ***/
    827 user_pref("privacy.resistFingerprinting.letterboxing", true); // [HIDDEN PREF]
    828    // user_pref("privacy.resistFingerprinting.letterboxing.dimensions", ""); // [HIDDEN PREF]
    829 /* 4505: experimental RFP [FF91+]
    830  * [WARNING] DO NOT USE unless testing, see [1] comment 12
    831  * [1] https://bugzilla.mozilla.org/1635603 ***/
    832    // user_pref("privacy.resistFingerprinting.exemptedDomains", "*.example.invalid");
    833 /* 4506: disable RFP spoof english prompt [FF59+]
    834  * 0=prompt, 1=disabled, 2=enabled (requires RFP)
    835  * [NOTE] When changing from value 2, preferred languages ('intl.accept_languages') is not reset.
    836  * [SETUP-WEB] when enabled, sets 'en-US, en' for displaying pages and 'en-US' as locale.
    837  * [SETTING] General>Language>Choose your preferred language for displaying pages>Choose>Request English... ***/
    838 user_pref("privacy.spoof_english", 1);
    839 /* 4510: disable using system colors
    840  * [SETTING] General>Language and Appearance>Fonts and Colors>Colors>Use system colors ***/
    841 user_pref("browser.display.use_system_colors", false); // [DEFAULT: false NON-WINDOWS]
    842 /* 4511: enforce non-native widget theme
    843  * Security: removes/reduces system API calls, e.g. win32k API [1]
    844  * Fingerprinting: provides a uniform look and feel across platforms [2]
    845  * [1] https://bugzilla.mozilla.org/1381938
    846  * [2] https://bugzilla.mozilla.org/1411425 ***/
    847 user_pref("widget.non-native-theme.enabled", true); // [DEFAULT: true]
    848 /* 4512: enforce links targeting new windows to open in a new tab instead
    849  * 1=most recent window or tab, 2=new window, 3=new tab
    850  * Stops malicious window sizes and some screen resolution leaks.
    851  * You can still right-click a link and open in a new window
    852  * [SETTING] General>Tabs>Open links in tabs instead of new windows
    853  * [TEST] https://arkenfox.github.io/TZP/tzp.html#screen
    854  * [1] https://gitlab.torproject.org/tpo/applications/tor-browser/-/issues/9881 ***/
    855 user_pref("browser.link.open_newwindow", 3); // [DEFAULT: 3]
    856 /* 4513: set all open window methods to abide by "browser.link.open_newwindow" (4512)
    857  * [1] https://searchfox.org/mozilla-central/source/dom/tests/browser/browser_test_new_window_from_content.js ***/
    858 user_pref("browser.link.open_newwindow.restriction", 0);
    859 /* 4520: disable WebGL (Web Graphics Library)
    860  * [SETUP-WEB] If you need it then override it. RFP still randomizes canvas for naive scripts ***/
    861 user_pref("webgl.disabled", true);
    862 
    863 /*** [SECTION 5000]: OPTIONAL OPSEC
    864    Disk avoidance, application data isolation, eyeballs...
    865 ***/
    866 user_pref("_user.js.parrot", "5000 syntax error: the parrot's taken 'is last bow");
    867 /* 5001: start Firefox in PB (Private Browsing) mode
    868  * [NOTE] In this mode all windows are "private windows" and the PB mode icon is not displayed
    869  * [NOTE] The P in PB mode can be misleading: it means no "persistent" disk state such as history,
    870  * caches, searches, cookies, localStorage, IndexedDB etc (which you can achieve in normal mode).
    871  * In fact, PB mode limits or removes the ability to control some of these, and you need to quit
    872  * Firefox to clear them. PB is best used as a one off window (Menu>New Private Window) to provide
    873  * a temporary self-contained new session. Close all private windows to clear the PB session.
    874  * [SETTING] Privacy & Security>History>Custom Settings>Always use private browsing mode
    875  * [1] https://wiki.mozilla.org/Private_Browsing
    876  * [2] https://support.mozilla.org/kb/common-myths-about-private-browsing ***/
    877    // user_pref("browser.privatebrowsing.autostart", true);
    878 /* 5002: disable memory cache
    879  * capacity: -1=determine dynamically (default), 0=none, n=memory capacity in kibibytes ***/
    880    // user_pref("browser.cache.memory.enable", false);
    881    // user_pref("browser.cache.memory.capacity", 0);
    882 /* 5003: disable saving passwords
    883  * [NOTE] This does not clear any passwords already saved
    884  * [SETTING] Privacy & Security>Logins and Passwords>Ask to save logins and passwords for websites ***/
    885    // user_pref("signon.rememberSignons", false);
    886 /* 5004: disable permissions manager from writing to disk [FF41+] [RESTART]
    887  * [NOTE] This means any permission changes are session only
    888  * [1] https://bugzilla.mozilla.org/967812 ***/
    889    // user_pref("permissions.memory_only", true); // [HIDDEN PREF]
    890 /* 5005: disable intermediate certificate caching [FF41+] [RESTART]
    891  * [NOTE] This affects login/cert/key dbs. The effect is all credentials are session-only.
    892  * Saved logins and passwords are not available. Reset the pref and restart to return them ***/
    893    // user_pref("security.nocertdb", true);
    894 /* 5006: disable favicons in history and bookmarks
    895  * [NOTE] Stored as data blobs in favicons.sqlite, these don't reveal anything that your
    896  * actual history (and bookmarks) already do. Your history is more detailed, so
    897  * control that instead; e.g. disable history, clear history on exit, use PB mode
    898  * [NOTE] favicons.sqlite is sanitized on Firefox close ***/
    899    // user_pref("browser.chrome.site_icons", false);
    900 /* 5007: exclude "Undo Closed Tabs" in Session Restore ***/
    901    // user_pref("browser.sessionstore.max_tabs_undo", 0);
    902 /* 5008: disable resuming session from crash
    903  * [TEST] about:crashparent ***/
    904    // user_pref("browser.sessionstore.resume_from_crash", false);
    905 /* 5009: disable "open with" in download dialog [FF50+]
    906  * Application data isolation [1]
    907  * [1] https://bugzilla.mozilla.org/1281959 ***/
    908    // user_pref("browser.download.forbid_open_with", true);
    909 /* 5010: disable location bar suggestion types
    910  * [SETTING] Search>Address Bar>When using the address bar, suggest ***/
    911    // user_pref("browser.urlbar.suggest.history", false);
    912    // user_pref("browser.urlbar.suggest.bookmark", false);
    913    // user_pref("browser.urlbar.suggest.openpage", false);
    914    // user_pref("browser.urlbar.suggest.topsites", false); // [FF78+]
    915 /* 5011: disable location bar dropdown
    916  * This value controls the total number of entries to appear in the location bar dropdown ***/
    917    // user_pref("browser.urlbar.maxRichResults", 0);
    918 /* 5012: disable location bar autofill
    919  * [1] https://support.mozilla.org/kb/address-bar-autocomplete-firefox#w_url-autocomplete ***/
    920    // user_pref("browser.urlbar.autoFill", false);
    921 /* 5013: disable browsing and download history
    922  * [NOTE] We also clear history and downloads on exit (2811)
    923  * [SETTING] Privacy & Security>History>Custom Settings>Remember browsing and download history ***/
    924    // user_pref("places.history.enabled", false);
    925 /* 5014: disable Windows jumplist [WINDOWS] ***/
    926    // user_pref("browser.taskbar.lists.enabled", false);
    927    // user_pref("browser.taskbar.lists.frequent.enabled", false);
    928    // user_pref("browser.taskbar.lists.recent.enabled", false);
    929    // user_pref("browser.taskbar.lists.tasks.enabled", false);
    930 /* 5016: discourage downloading to desktop
    931  * 0=desktop, 1=downloads (default), 2=custom
    932  * [SETTING] To set your custom default "downloads": General>Downloads>Save files to ***/
    933    // user_pref("browser.download.folderList", 2);
    934 /* 5017: disable Form Autofill
    935  * If .supportedCountries includes your region (browser.search.region) and .supported
    936  * is "detect" (default), then the UI will show. Stored data is not secure, uses JSON
    937  * [SETTING] Privacy & Security>Forms and Autofill>Autofill addresses
    938  * [1] https://wiki.mozilla.org/Firefox/Features/Form_Autofill ***/
    939    // user_pref("extensions.formautofill.addresses.enabled", false); // [FF55+]
    940    // user_pref("extensions.formautofill.creditCards.enabled", false); // [FF56+]
    941 /* 5018: limit events that can cause a pop-up ***/
    942    // user_pref("dom.popup_allowed_events", "click dblclick mousedown pointerdown");
    943 /* 5019: disable page thumbnail collection ***/
    944    // user_pref("browser.pagethumbnails.capturing_disabled", true); // [HIDDEN PREF]
    945 /* 5020: disable Windows native notifications and use app notications instead [FF111+] [WINDOWS] ***/
    946    // user_pref("alerts.useSystemBackend.windows.notificationserver.enabled", false);
    947 /* 5021: disable location bar using search
    948  * Don't leak URL typos to a search engine, give an error message instead
    949  * Examples: "secretplace,com", "secretplace/com", "secretplace com", "secret place.com"
    950  * [NOTE] This does not affect explicit user action such as using search buttons in the
    951  * dropdown, or using keyword search shortcuts you configure in options (e.g. "d" for DuckDuckGo) ***/
    952    // user_pref("keyword.enabled", false);
    953 
    954 /*** [SECTION 5500]: OPTIONAL HARDENING
    955    Not recommended. Overriding these can cause breakage and performance issues,
    956    they are mostly fingerprintable, and the threat model is practically nonexistent
    957 ***/
    958 user_pref("_user.js.parrot", "5500 syntax error: this is an ex-parrot!");
    959 /* 5501: disable MathML (Mathematical Markup Language) [FF51+]
    960  * [1] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=mathml ***/
    961    // user_pref("mathml.disabled", true); // 1173199
    962 /* 5502: disable in-content SVG (Scalable Vector Graphics) [FF53+]
    963  * [1] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=firefox+svg ***/
    964    // user_pref("svg.disabled", true); // 1216893
    965 /* 5503: disable graphite
    966  * [1] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=firefox+graphite
    967  * [2] https://en.wikipedia.org/wiki/Graphite_(SIL) ***/
    968    // user_pref("gfx.font_rendering.graphite.enabled", false);
    969 /* 5504: disable asm.js [FF22+]
    970  * [1] http://asmjs.org/
    971  * [2] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=asm.js
    972  * [3] https://rh0dev.github.io/blog/2017/the-return-of-the-jit/ ***/
    973    // user_pref("javascript.options.asmjs", false);
    974 /* 5505: disable Ion and baseline JIT to harden against JS exploits
    975  * [NOTE] When both Ion and JIT are disabled, and trustedprincipals
    976  * is enabled, then Ion can still be used by extensions (1599226)
    977  * [1] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=firefox+jit
    978  * [2] https://microsoftedge.github.io/edgevr/posts/Super-Duper-Secure-Mode/ ***/
    979    // user_pref("javascript.options.ion", false);
    980    // user_pref("javascript.options.baselinejit", false);
    981    // user_pref("javascript.options.jit_trustedprincipals", true); // [FF75+] [HIDDEN PREF]
    982 /* 5506: disable WebAssembly [FF52+]
    983  * Vulnerabilities [1] have increasingly been found, including those known and fixed
    984  * in native programs years ago [2]. WASM has powerful low-level access, making
    985  * certain attacks (brute-force) and vulnerabilities more possible
    986  * [STATS] ~0.2% of websites, about half of which are for cryptomining / malvertising [2][3]
    987  * [1] https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=wasm
    988  * [2] https://spectrum.ieee.org/tech-talk/telecom/security/more-worries-over-the-security-of-web-assembly
    989  * [3] https://www.zdnet.com/article/half-of-the-websites-using-webassembly-use-it-for-malicious-purposes ***/
    990    // user_pref("javascript.options.wasm", false);
    991 /* 5507: disable rendering of SVG OpenType fonts ***/
    992    // user_pref("gfx.font_rendering.opentype_svg.enabled", false);
    993 /* 5508: disable all DRM content (EME: Encryption Media Extension)
    994  * Optionally hide the UI setting which also disables the DRM prompt
    995  * [SETTING] General>DRM Content>Play DRM-controlled content
    996  * [TEST] https://bitmovin.com/demos/drm
    997  * [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 ***/
    998    // user_pref("media.eme.enabled", false);
    999    // user_pref("browser.eme.ui.enabled", false);
   1000 /* 5509: disable IPv6 if using a VPN
   1001  * This is an application level fallback. Disabling IPv6 is best done at an OS/network
   1002  * level, and/or configured properly in system wide VPN setups.
   1003  * [SETUP-WEB] PR_CONNECT_RESET_ERROR
   1004  * [NOTE] PHP defaults to IPv6 with "localhost". Use "php -S 127.0.0.1:PORT"
   1005  * [TEST] https://ipleak.org/
   1006  * [1] https://www.internetsociety.org/tag/ipv6-security/ (Myths 2,4,5,6) ***/
   1007    // user_pref("network.dns.disableIPv6", true);
   1008 /* 5510: control when to send a cross-origin referer
   1009  * 0=always (default), 1=only if base domains match, 2=only if hosts match
   1010  * [NOTE] Will cause breakage: older modems/routers and some sites e.g banks, vimeo, icloud, instagram ***/
   1011    // user_pref("network.http.referer.XOriginPolicy", 2);
   1012 /* 5511: set DoH bootstrap address [FF89+]
   1013  * Firefox uses the system DNS to initially resolve the IP address of your DoH server.
   1014  * When set to a valid, working value that matches your "network.trr.uri" (0712) Firefox
   1015  * won't use the system DNS. If the IP doesn't match then DoH won't work ***/
   1016    // user_pref("network.trr.bootstrapAddr", "10.0.0.1"); // [HIDDEN PREF]
   1017 
   1018 /*** [SECTION 6000]: DON'T TOUCH ***/
   1019 user_pref("_user.js.parrot", "6000 syntax error: the parrot's 'istory!");
   1020 /* 6001: enforce Firefox blocklist
   1021  * [WHY] It includes updates for "revoked certificates"
   1022  * [1] https://blog.mozilla.org/security/2015/03/03/revoking-intermediate-certificates-introducing-onecrl/ ***/
   1023 user_pref("extensions.blocklist.enabled", true); // [DEFAULT: true]
   1024 /* 6002: enforce no referer spoofing
   1025  * [WHY] Spoofing can affect CSRF (Cross-Site Request Forgery) protections ***/
   1026 user_pref("network.http.referer.spoofSource", false); // [DEFAULT: false]
   1027 /* 6004: enforce a security delay on some confirmation dialogs such as install, open/save
   1028  * [1] https://www.squarefree.com/2004/07/01/race-conditions-in-security-dialogs/ ***/
   1029 user_pref("security.dialog_enable_delay", 1000); // [DEFAULT: 1000]
   1030 /* 6008: enforce no First Party Isolation [FF51+]
   1031  * [WARNING] Replaced with network partitioning (FF85+) and TCP (2701), and enabling FPI
   1032  * disables those. FPI is no longer maintained except at Tor Project for Tor Browser's config ***/
   1033 user_pref("privacy.firstparty.isolate", false); // [DEFAULT: false]
   1034 /* 6009: enforce SmartBlock shims (about:compat) [FF81+]
   1035  * [1] https://blog.mozilla.org/security/2021/03/23/introducing-smartblock/ ***/
   1036 user_pref("extensions.webcompat.enable_shims", true); // [HIDDEN PREF] [DEFAULT: true]
   1037 /* 6010: enforce no TLS 1.0/1.1 downgrades
   1038  * [TEST] https://tls-v1-1.badssl.com:1010/ ***/
   1039 user_pref("security.tls.version.enable-deprecated", false); // [DEFAULT: false]
   1040 /* 6011: enforce disabling of Web Compatibility Reporter [FF56+]
   1041  * Web Compatibility Reporter adds a "Report Site Issue" button to send data to Mozilla
   1042  * [WHY] To prevent wasting Mozilla's time with a custom setup ***/
   1043 user_pref("extensions.webcompat-reporter.enabled", false); // [DEFAULT: false]
   1044 /* 6012: enforce Quarantined Domains [FF115+]
   1045  * [WHY] https://support.mozilla.org/kb/quarantined-domains */
   1046 user_pref("extensions.quarantinedDomains.enabled", true); // [DEFAULT: true]
   1047 /* 6050: prefsCleaner: previously active items removed from arkenfox 115-127 ***/
   1048    // user_pref("accessibility.force_disabled", "");
   1049    // user_pref("browser.urlbar.dnsResolveSingleWordsAfterSearch", "");
   1050    // user_pref("network.protocol-handler.external.ms-windows-store", "");
   1051    // user_pref("privacy.partition.always_partition_third_party_non_cookie_storage", "");
   1052    // user_pref("privacy.partition.always_partition_third_party_non_cookie_storage.exempt_sessionstorage", "");
   1053    // user_pref("privacy.partition.serviceWorkers", "");
   1054 
   1055 /*** [SECTION 7000]: DON'T BOTHER ***/
   1056 user_pref("_user.js.parrot", "7000 syntax error: the parrot's pushing up daisies!");
   1057 /* 7001: disable APIs
   1058  * Location-Aware Browsing, Full Screen
   1059  * [WHY] The API state is easily fingerprintable.
   1060  * Geo is behind a prompt (7002). Full screen requires user interaction ***/
   1061    // user_pref("geo.enabled", false);
   1062    // user_pref("full-screen-api.enabled", false);
   1063 /* 7002: set default permissions
   1064  * Location, Camera, Microphone, Notifications [FF58+] Virtual Reality [FF73+]
   1065  * 0=always ask (default), 1=allow, 2=block
   1066  * [WHY] These are fingerprintable via Permissions API, except VR. Just add site
   1067  * exceptions as allow/block for frequently visited/annoying sites: i.e. not global
   1068  * [SETTING] to add site exceptions: Ctrl+I>Permissions>
   1069  * [SETTING] to manage site exceptions: Options>Privacy & Security>Permissions>Settings ***/
   1070    // user_pref("permissions.default.geo", 0);
   1071    // user_pref("permissions.default.camera", 0);
   1072    // user_pref("permissions.default.microphone", 0);
   1073    // user_pref("permissions.default.desktop-notification", 0);
   1074    // user_pref("permissions.default.xr", 0); // Virtual Reality
   1075 /* 7003: disable non-modern cipher suites [1]
   1076  * [WHY] Passive fingerprinting. Minimal/non-existent threat of downgrade attacks
   1077  * [1] https://browserleaks.com/ssl ***/
   1078    // user_pref("security.ssl3.ecdhe_ecdsa_aes_128_sha", false);
   1079    // user_pref("security.ssl3.ecdhe_ecdsa_aes_256_sha", false);
   1080    // user_pref("security.ssl3.ecdhe_rsa_aes_128_sha", false);
   1081    // user_pref("security.ssl3.ecdhe_rsa_aes_256_sha", false);
   1082    // user_pref("security.ssl3.rsa_aes_128_gcm_sha256", false); // no PFS
   1083    // user_pref("security.ssl3.rsa_aes_256_gcm_sha384", false); // no PFS
   1084    // user_pref("security.ssl3.rsa_aes_128_sha", false); // no PFS
   1085    // user_pref("security.ssl3.rsa_aes_256_sha", false); // no PFS
   1086 /* 7004: control TLS versions
   1087  * [WHY] Passive fingerprinting and security ***/
   1088    // user_pref("security.tls.version.min", 3); // [DEFAULT: 3]
   1089    // user_pref("security.tls.version.max", 4);
   1090 /* 7005: disable SSL session IDs [FF36+]
   1091  * [WHY] Passive fingerprinting and perf costs. These are session-only
   1092  * and isolated with network partitioning (FF85+) and/or containers ***/
   1093    // user_pref("security.ssl.disable_session_identifiers", true);
   1094 /* 7006: onions
   1095  * [WHY] Firefox doesn't support hidden services. Use Tor Browser ***/
   1096    // user_pref("dom.securecontext.allowlist_onions", true); // [FF97+] 1382359/1744006
   1097    // user_pref("network.http.referer.hideOnionSource", true); // 1305144
   1098 /* 7007: referers
   1099  * [WHY] Only cross-origin referers (1602, 5510) matter ***/
   1100    // user_pref("network.http.sendRefererHeader", 2);
   1101    // user_pref("network.http.referer.trimmingPolicy", 0);
   1102 /* 7008: set the default Referrer Policy [FF59+]
   1103  * 0=no-referer, 1=same-origin, 2=strict-origin-when-cross-origin, 3=no-referrer-when-downgrade
   1104  * [WHY] Defaults are fine. They can be overridden by a site-controlled Referrer Policy ***/
   1105    // user_pref("network.http.referer.defaultPolicy", 2); // [DEFAULT: 2]
   1106    // user_pref("network.http.referer.defaultPolicy.pbmode", 2); // [DEFAULT: 2]
   1107 /* 7010: disable HTTP Alternative Services [FF37+]
   1108  * [WHY] Already isolated with network partitioning (FF85+) ***/
   1109    // user_pref("network.http.altsvc.enabled", false);
   1110 /* 7011: disable website control over browser right-click context menu
   1111  * [WHY] Just use Shift-Right-Click ***/
   1112    // user_pref("dom.event.contextmenu.enabled", false);
   1113 /* 7012: disable icon fonts (glyphs) and local fallback rendering
   1114  * [WHY] Breakage, font fallback is equivalency, also RFP
   1115  * [1] https://bugzilla.mozilla.org/789788
   1116  * [2] https://gitlab.torproject.org/legacy/trac/-/issues/8455 ***/
   1117    // user_pref("gfx.downloadable_fonts.enabled", false); // [FF41+]
   1118    // user_pref("gfx.downloadable_fonts.fallback_delay", -1);
   1119 /* 7013: disable Clipboard API
   1120  * [WHY] Fingerprintable. Breakage. Cut/copy/paste require user
   1121  * interaction, and paste is limited to focused editable fields ***/
   1122    // user_pref("dom.event.clipboardevents.enabled", false);
   1123 /* 7014: disable System Add-on updates
   1124  * [WHY] It can compromise security. System addons ship with prefs, use those ***/
   1125    // user_pref("extensions.systemAddon.update.enabled", false); // [FF62+]
   1126    // user_pref("extensions.systemAddon.update.url", ""); // [FF44+]
   1127 /* 7015: enable the DNT (Do Not Track) HTTP header
   1128  * [WHY] DNT is enforced with Tracking Protection which is used in ETP Strict (2701) ***/
   1129    // user_pref("privacy.donottrackheader.enabled", true);
   1130 /* 7016: customize ETP settings
   1131  * [NOTE] FPP (fingerprintingProtection) is ignored when RFP (4501) is enabled
   1132  * [WHY] Arkenfox only supports strict (2701) which sets these at runtime ***/
   1133    // user_pref("network.cookie.cookieBehavior", 5); // [DEFAULT: 5]
   1134    // user_pref("privacy.fingerprintingProtection", true); // [FF114+] [ETP FF119+]
   1135    // user_pref("network.http.referer.disallowCrossSiteRelaxingDefault", true);
   1136    // user_pref("network.http.referer.disallowCrossSiteRelaxingDefault.top_navigation", true); // [FF100+]
   1137    // user_pref("privacy.partition.network_state.ocsp_cache", true); // [DEFAULT: true FF123+]
   1138    // user_pref("privacy.query_stripping.enabled", true); // [FF101+]
   1139    // user_pref("privacy.trackingprotection.enabled", true);
   1140    // user_pref("privacy.trackingprotection.socialtracking.enabled", true);
   1141    // user_pref("privacy.trackingprotection.cryptomining.enabled", true); // [DEFAULT: true]
   1142    // user_pref("privacy.trackingprotection.fingerprinting.enabled", true); // [DEFAULT: true]
   1143 /* 7017: disable service workers
   1144  * [WHY] Already isolated with TCP (2701) behind a pref (2710) ***/
   1145    // user_pref("dom.serviceWorkers.enabled", false);
   1146 /* 7018: disable Web Notifications [FF22+]
   1147  * [WHY] Web Notifications are behind a prompt (7002)
   1148  * [1] https://blog.mozilla.org/en/products/firefox/block-notification-requests/ ***/
   1149    // user_pref("dom.webnotifications.enabled", false);
   1150 /* 7019: disable Push Notifications [FF44+]
   1151  * [WHY] Website "push" requires subscription, and the API is required for CRLite (1224)
   1152  * [NOTE] To remove all subscriptions, reset "dom.push.userAgentID"
   1153  * [1] https://support.mozilla.org/kb/push-notifications-firefox ***/
   1154    // user_pref("dom.push.enabled", false);
   1155 /* 7020: disable WebRTC (Web Real-Time Communication)
   1156  * [WHY] Firefox desktop uses mDNS hostname obfuscation and the private IP is never exposed until
   1157  * required in TRUSTED scenarios; i.e. after you grant device (microphone or camera) access
   1158  * [TEST] https://browserleaks.com/webrtc
   1159  * [1] https://groups.google.com/g/discuss-webrtc/c/6stQXi72BEU/m/2FwZd24UAQAJ
   1160  * [2] https://datatracker.ietf.org/doc/html/draft-ietf-mmusic-mdns-ice-candidates#section-3.1.1 ***/
   1161    // user_pref("media.peerconnection.enabled", false);
   1162 /* 7021: enable GPC (Global Privacy Control) in non-PB windows
   1163  * [WHY] Passive and active fingerprinting. Mostly redundant with Tracking Protection
   1164  * in ETP Strict (2701) and sanitizing on close (2800s) ***/
   1165    // user_pref("privacy.globalprivacycontrol.enabled", true);
   1166 
   1167 /*** [SECTION 8000]: DON'T BOTHER: FINGERPRINTING
   1168    [WHY] They are insufficient to help anti-fingerprinting and do more harm than good
   1169    [WARNING] DO NOT USE with RFP. RFP already covers these and they can interfere
   1170 ***/
   1171 user_pref("_user.js.parrot", "8000 syntax error: the parrot's crossed the Jordan");
   1172 /* 8001: prefsCleaner: reset items useless for anti-fingerprinting ***/
   1173    // user_pref("browser.display.use_document_fonts", "");
   1174    // user_pref("browser.zoom.siteSpecific", "");
   1175    // user_pref("device.sensors.enabled", "");
   1176    // user_pref("dom.enable_performance", "");
   1177    // user_pref("dom.enable_resource_timing", "");
   1178    // user_pref("dom.gamepad.enabled", "");
   1179    // user_pref("dom.maxHardwareConcurrency", "");
   1180    // user_pref("dom.w3c_touch_events.enabled", "");
   1181    // user_pref("dom.webaudio.enabled", "");
   1182    // user_pref("font.system.whitelist", "");
   1183    // user_pref("general.appname.override", "");
   1184    // user_pref("general.appversion.override", "");
   1185    // user_pref("general.buildID.override", "");
   1186    // user_pref("general.oscpu.override", "");
   1187    // user_pref("general.platform.override", "");
   1188    // user_pref("general.useragent.override", "");
   1189    // user_pref("media.navigator.enabled", "");
   1190    // user_pref("media.ondevicechange.enabled", "");
   1191    // user_pref("media.video_stats.enabled", "");
   1192    // user_pref("media.webspeech.synth.enabled", "");
   1193    // user_pref("ui.use_standins_for_native_colors", "");
   1194    // user_pref("webgl.enable-debug-renderer-info", "");
   1195 
   1196 /*** [SECTION 9000]: NON-PROJECT RELATED ***/
   1197 user_pref("_user.js.parrot", "9000 syntax error: the parrot's cashed in 'is chips!");
   1198 /* 9001: disable welcome notices ***/
   1199 user_pref("browser.startup.homepage_override.mstone", "ignore"); // [HIDDEN PREF]
   1200 /* 9002: disable General>Browsing>Recommend extensions/features as you browse [FF67+] ***/
   1201 user_pref("browser.newtabpage.activity-stream.asrouter.userprefs.cfr.addons", false);
   1202 user_pref("browser.newtabpage.activity-stream.asrouter.userprefs.cfr.features", false);
   1203 /* 9004: disable search terms [FF110+]
   1204  * [SETTING] Search>Search Bar>Use the address bar for search and navigation>Show search terms instead of URL... ***/
   1205 user_pref("browser.urlbar.showSearchTerms.enabled", false);
   1206 
   1207 /*** [SECTION 9999]: DEPRECATED / RENAMED ***/
   1208 user_pref("_user.js.parrot", "9999 syntax error: the parrot's shuffled off 'is mortal coil!");
   1209 /* ESR115.x still uses all the following prefs
   1210 // [NOTE] replace the * with a slash in the line above to re-enable active ones
   1211 // FF116
   1212 // 4506: set RFP's font visibility level (1402) [FF94+]
   1213    // [-] https://bugzilla.mozilla.org/1838415
   1214    // user_pref("layout.css.font-visibility.resistFingerprinting", 1); // [DEFAULT: 1]
   1215 // FF117
   1216 // 1221: disable Windows Microsoft Family Safety cert [FF50+] [WINDOWS]
   1217    // 0=disable detecting Family Safety mode and importing the root
   1218    // 1=only attempt to detect Family Safety mode (don't import the root)
   1219    // 2=detect Family Safety mode and import the root
   1220    // [1] https://gitlab.torproject.org/tpo/applications/tor-browser/-/issues/21686
   1221    // [-] https://bugzilla.mozilla.org/1844908
   1222 user_pref("security.family_safety.mode", 0);
   1223 // 7018: disable service worker Web Notifications [FF44+]
   1224    // [WHY] Web Notifications are behind a prompt (7002)
   1225    // [1] https://blog.mozilla.org/en/products/firefox/block-notification-requests/
   1226    // [-] https://bugzilla.mozilla.org/1842457
   1227    // user_pref("dom.webnotifications.serviceworker.enabled", false);
   1228 // FF118
   1229 // 1402: limit font visibility (Windows, Mac, some Linux) [FF94+]
   1230    // Uses hardcoded lists with two parts: kBaseFonts + kLangPackFonts [1], bundled fonts are auto-allowed
   1231    // In normal windows: uses the first applicable: RFP over TP over Standard
   1232    // In Private Browsing windows: uses the most restrictive between normal and private
   1233    // 1=only base system fonts, 2=also fonts from optional language packs, 3=also user-installed fonts
   1234    // [1] https://searchfox.org/mozilla-central/search?path=StandardFonts*.inc
   1235    // [-] https://bugzilla.mozilla.org/1847599
   1236    // user_pref("layout.css.font-visibility.private", 1);
   1237    // user_pref("layout.css.font-visibility.standard", 1);
   1238    // user_pref("layout.css.font-visibility.trackingprotection", 1);
   1239 // 2623: disable permissions delegation [FF73+]
   1240    // Currently applies to cross-origin geolocation, camera, mic and screen-sharing
   1241    // permissions, and fullscreen requests. Disabling delegation means any prompts
   1242    // for these will show/use their correct 3rd party origin
   1243    // [1] https://groups.google.com/forum/#!topic/mozilla.dev.platform/BdFOMAuCGW8/discussion
   1244    // [-] https://bugzilla.mozilla.org/1697151
   1245    // user_pref("permissions.delegation.enabled", false);
   1246 // FF119
   1247 // 0211: use en-US locale regardless of the system or region locale
   1248    // [SETUP-WEB] May break some input methods e.g xim/ibus for CJK languages [1]
   1249    // [1] https://bugzilla.mozilla.org/buglist.cgi?bug_id=867501,1629630
   1250    // [-] https://bugzilla.mozilla.org/1846224
   1251    // user_pref("javascript.use_us_english_locale", true); // [HIDDEN PREF]
   1252 // 0711: disable skipping DoH when parental controls are enabled [FF70+]
   1253    // [-] https://bugzilla.mozilla.org/1586941
   1254 user_pref("network.dns.skipTRR-when-parental-control-enabled", false);
   1255 // FF123
   1256 // 0334: disable PingCentre telemetry (used in several System Add-ons) [FF57+]
   1257    // Defense-in-depth: currently covered by 0331
   1258    // [-] https://bugzilla.mozilla.org/1868988
   1259 user_pref("browser.ping-centre.telemetry", false);
   1260 // FF126
   1261 // 9003: disable What's New toolbar icon [FF69+]
   1262    // [-] https://bugzilla.mozilla.org/1724300
   1263 user_pref("browser.messaging-system.whatsNewPanel.enabled", false);
   1264 // ***/
   1265 
   1266 /* END: internal custom pref to test for syntax errors ***/
   1267 user_pref("_user.js.parrot", "SUCCESS: No no he's not dead, he's, he's restin'!");