Userscript to tighten security in Mozilla Firefox

Question

I have recently started writing a userscript for Mozilla Firefox to tighten security and make it more private, but before I want to start publishing it, I would like to have some experts take a look at it to see if I made any mistakes, I am by no means a experienced coder, and this is my first little project. Things I am looking for are tips to make my code easier to read and if I have any missing crypto suites (again if this is the wrong way to ask this then please feel free to correct me and say what I should say).

I will also post a link to the GitHub paste since its easier to read there.

// firefox privacy setup, last time edited: 5 10 2016 //
// geo switches //
// Preference name Value //
user_pref("geo.enabled", false);
user_pref("geo.wifi.logging.enabled", false);
user_pref("geo.wifi.uri", "http://127.0.0.1");
// media switches //
// Preference name Value //
user_pref("media.peerconnection.ice.default_address_only" true);
user_pref("media.peerconnection.enabled",		 false);
user_pref("media.navigator.enabled", false);
user_pref("media.webspeech.recognition.enable", false);
user_pref("media.getusermedia.screensharing.enabled",		false);
user_pref("media.getusermedia.screensharing.allowed_domains", "");
user_pref("media.eme.enabled", false);
user_pref("media.eme.apiVisible", false);
user_pref("media.gmp-eme-adobe.enabled", false);
user_pref("media.video_stats.enabled", false);
user_pref("media.gmp-gmpopenh264.enabled",		 false);
user_pref("media.gmp-manager.url",		 "");
user_pref("media.gmp-provider.enabled", false);
user_pref("media.peerconnection.turn.disable", true);
user_pref("media.peerconnection.use_document_iceservers", false);
user_pref("media.peerconnection.video.enabled", false);
user_pref("media.peerconnection.identity.timeout", false);
user_pref("media.autoplay.enabled", false);
user_pref("media.getusermedia.screensharing.allowed_domains", "");
// device switches //
// Preference name Value //
user_pref("device.sensors.enabled", false);
// camera switches //
// Preference name Value //
user_pref("camera.control.face_detection.enabled", false);
user_pref("camera.contro.autofocus_moving_callback.enabled", false);
// devtool switches //
// Preference name Value //
user_pref("devtools.webide.autoinstallADBHelper", false);
user_pref("devtools.webide.autoinstallFxdtAdapters", false);
user_pref("devtools.debugger.remote-enabled", false);
user_pref("devtools.webide.enabled", false);
user_pref("devtools.chrome.enabled", false);
user_pref("devtools.debugger.force-local", true);
// network switches //
// Preference name Value //
user_pref("network.http.spdy.enabled", false); 
user_pref("network.http.spdy.enabled.v3", false);
user_pref("network.http.spdy.enabled.v3-1", false);
user_pref("network.http.spdy.enabled.http2", false);
user_pref("network.proxy.socks_remote_dns", true);
user_pref("network.jar.open-unsafe-types",		 false);
user_pref("network.prefetch-next",		 false);
user_pref("network.dns.disablePrefetch",		 true);
user_pref("network.dns.disablePrefetchFromHTTPS",		true);
user_pref("network.predictor.enabled", false);
user_pref("network.seer.enabled", false);
user_pref("network.http.speculative-parallel-limit",		0);
user_pref("network.negotiate-auth.allow-insecure-ntlm-v1", false);
user_pref("network.http.referer.spoofSource", true);
user_pref("network.cookie.cookieBehavior", 2);
user_pref("network.cookie.thirdparty.sessionOnly",		true);
user_pref("network.cookie.lifetimePolicy", 2);
user_pref("network.stricttransportsecurity.preloadlist", true);
user_pref("network.http.sendSecureXSiteReferrer", false);
user_pref("network.http.redirection-limit", 10);
user_pref("network.http.sendSecureXSiteReferrer", false);
user_pref("network.http.proxy.keep-alive", false);
user_pref("network.IDN_show_punycode", true);
user_pref("Network.cookie.p3p", "frfrarar");
user_pref("network.allow-experiments", false);
// plugin(s) switches //
// Preference name Value //
user_pref("plugin.state.flash",		 0);
user_pref("plugin.state.libgnome-shell-browser-plugin", 0);
user_pref("plugins.click_to_play", true);
user_pref("plugins.update.notifyUser",		 true);
user_pref("plugins.hide_infobar_for_outdated_plugin",		false);
user_pref("plugin.scan.plid.all", false);
user_pref("plugin.scan.Acrobat", 99999);
user_pref("plugin.scan.Quicktime", 99999);
user_pref("plugin.scan.WindowsMediaPlayer", 99999);
user_pref("plugin.default.state", 0);
user_pref("plugin.defaultXpi.state", 0);
user_pref("plugin.sessionPermissionNow.intervalInMinutes", 0);
user_pref("plugins.notifyMissingFlash", false);
// javascript //
// Preference name Value //
user_pref("javascript.options.methodjit.chrome",		false);
user_pref("javascript.options.methodjit.content",		false);
user_pref("javascript.options.asmjs",		 false);
user_pref("javascript.enabled", false);
// datareport switches //
// Preference name Value //
user_pref("datareporting.healthreport.uploadEnabled", false);
user_pref("datareporting.healthreport.service.enabled", false);
user_pref("datareporting.policy.dataSubmissionEnabled", false);
user_pref("datareporting.healthreport.documentServerURI", "");
user_pref("datareporting.policy.dataSubmissionEnabled.v2", false);
user_pref("datareporting.healthreport.about.reportUrl", "");
user_pref("datareporting.healthreport.about.reportUrlUnified", "");
user_pref("datareporting.healthreport.documentServerURI", "");
// toolkit switches //
// Preference name Value //
user_pref("toolkit.telemetry.enabled", false);
user_pref("toolkit.telemetry.unified", false);
user_pref("toolkit.telemetry.server", "");
user_pref("toolkit.telemetry.archive.enabled", false);
user_pref("toolkit.telemetry.rejected", true);
user_pref("toolkit.telemetry.prompted", 2);
user_pref("toolkit.telemetry.cachedClientID", "");
// extension switches //
// Preference name Value //
user_pref("extensions.getAddons.cache.enabled", false);
user_pref("extensions.update.enabled", true);
user_pref("extensions.blocklist.enabled", true);
user_pref("extensions.webservice.discoverURL", "http://127.0.0.1");
// experiment switches //
// Preference name Value //
user_pref("experiments.supported",		 false);
user_pref("experiments.enabled",		 false);
user_pref("experiments.manifest.uri", "");
user_pref("experiments.activeExperiment", false);
// social switches //
// Preference name Value //
user_pref("social.whitelist", "");
user_pref("social.toast-notifications.enabled", false);
user_pref("social.shareDirectory", "");
user_pref("social.remote-install.enabled", false);
user_pref("social.directories", "");
user_pref("social.share.activationPanelEnabled", false);
// dom switches //
// Preference name Value //
user_pref("dom.storage.enabled", false);
user_pref("dom.indexedDB.enabled", true);
user_pref("dom.webnotifications.enabled", false);
user_pref("dom.webnotifications.serviceworker.enabled", false);
	 user_pref("dom.disable_image_src_set", true);
user_pref("dom.battery.enabled", false);
user_pref("dom.telephony.enabled", false);
user_pref("dom.event.clipboardevents.enabled", false);
user_pref("dom.enable_performance",		 false);
user_pref("dom.gamepad.enabled",		 false);
user_pref("dom.vibrator.enabled", false);
user_pref("dom.vr.enabled",		 false);
user_pref("dom.vr.oculus.enabled", false);
user_pref("dom.vr.oculus050.enabled", false);
user_pref("dom.netinfo.enabled", false);
user_pref("dom.network.enabled", false);
user_pref("dom.workers.sharedWorkers.enabled", false);
user_pref("dom.w3c_touch_events.enabled", 0);
user_pref("dom.enable_resource_timing", false);
user_pref("dom.enable_user_timing", false);
user_pref("dom.idle-observers-api.enabled", false);
user_pref("dom.webnotifications.enabled",		 false);
user_pref("dom.push.connection.enabled", false);
user_pref("dom.push.serverURL", "");
user_pref("dom.push.udp.wakeupEnabled", false);
user_pref("dom.push.userAgentID", "");
user_pref("dom.push.enabled", false);
user_pref("dom.disable_beforeunload", true);
user_pref("dom.push.enabled", false);
user_pref("dom.event.contextmenu.enabled", false);
user_pref("dom.disable_window_open_feature.location", true); 
user_pref("dom.disable_window_open_feature.menubar", true);
user_pref("dom.disable_window_open_feature.resizable", true);
user_pref("dom.disable_window_open_feature.scrollbars", true);
user_pref("dom.disable_window_open_feature.status", true);
user_pref("dom.disable_window_open_feature.toolbar", true);
user_pref("dom.disable_window_flip", true); 
user_pref("dom.disable_window_move_resize", true);
user_pref("dom.disable_window_open_feature.close", true);
user_pref("dom.disable_window_open_feature.minimizable", true);
user_pref("dom.disable_window_open_feature.personalbar", true); 
user_pref("dom.disable_window_open_feature.titlebar", true);
user_pref("dom.disable_window_status_change", true);
user_pref("dom.allow_scripts_to_close_windows", false);
user_pref("dom.ipc.plugins.enabled", false);
user_pref("dom.ipc.plugins.flash.subprocess.crashreporter.enabled", false);
// security switches //
// Preference name Value //
user_pref("security.mixed_content.block_active_content", true);
user_pref("security.mixed_content.block_display_content", true);
user_pref("security.xpconnect.plugin.unrestricted", false);
user_pref("security.fileuri.strict_origin_policy", true);
user_pref("security.csp.experimentalEnabled",		 true);
user_pref("security.csp.enable",		 true);
user_pref("security.sri.enable",		 true);
user_pref("security.mixed_content.block_active_content", true);
user_pref("security.dialog_enable_delay", 1000);
// security -crypto- switches //
// Preference name Value //
user_pref("security.warn_entering_weak",		 true);
user_pref("security.ssl.warn_missing_rfc5746", 1);
user_pref("security.OCSP.enabled", 1);
user_pref("security.ssl.enable_ocsp_stapling",		 true);
user_pref("security.OCSP.require", true);
user_pref("security.enable_tls_session_tickets", false);
user_pref("security.tls.version.min",		 3);
user_pref("security.tls.version.max",		 3);
user_pref("security.enable_ssl3", false);
user_pref("security.cert_pinning.enforcement_level", 2);
user_pref("security.pki.sha1_enforcement_level", 2);
user_pref("security.ssl.treat_unsafe_negotiation_as_broken", 	true);
user_pref("security.ssl.errorReporting.automatic", false);
user_pref("security.ssl.errorReporting.enabled", false);
user_pref("security.ssl.errorReporting.url", "");
user_pref("security.ssl3.rsa_null_sha",		 false);
user_pref("security.ssl3.rsa_null_md5",		 false);
user_pref("security.ssl3.ecdhe_rsa_null_sha",		 false);
user_pref("security.ssl3.ecdhe_ecdsa_null_sha",		 false);
user_pref("security.ssl3.ecdh_rsa_null_sha",		 false);
user_pref("security.ssl3.ecdh_ecdsa_null_sha",		 false);
user_pref("security.ssl3.rsa_seed_sha",		 false);
user_pref("security.ssl3.rsa_rc4_40_md5",		 false);
user_pref("security.ssl3.rsa_rc2_40_md5",		 false);
user_pref("security.ssl3.rsa_1024_rc4_56_sha", false);
user_pref("security.ssl3.rsa_camellia_128_sha",		 false);
user_pref("security.ssl3.ecdhe_rsa_aes_128_sha",		false);
user_pref("security.ssl3.ecdhe_ecdsa_aes_128_sha",		false);
user_pref("security.ssl3.ecdh_rsa_aes_128_sha",		 false);
user_pref("security.ssl3.ecdh_ecdsa_aes_128_sha",		false);
user_pref("security.ssl3.dhe_rsa_camellia_128_sha",		false);
user_pref("security.ssl3.dhe_rsa_aes_128_sha",		 false);
user_pref("security.ssl3.ecdh_ecdsa_rc4_128_sha",		false);
user_pref("security.ssl3.ecdh_rsa_rc4_128_sha",		 false);
user_pref("security.ssl3.ecdhe_ecdsa_rc4_128_sha",		false);
user_pref("security.ssl3.ecdhe_rsa_rc4_128_sha",		false);
user_pref("security.ssl3.rsa_rc4_128_md5",		 false);
user_pref("security.ssl3.rsa_rc4_128_sha",		 false);
user_pref("security.tls.unrestricted_rc4_fallback",		false);
user_pref("security.tls.insecure_safe_negotiation", false);
user_pref("security.ssl.require_safe_negotiation", true);
user_pref("security.ssl3.dhe_dss_des_ede3_sha",		 false);
user_pref("security.ssl3.dhe_rsa_des_ede3_sha",		 false);
user_pref("security.ssl3.ecdh_ecdsa_des_ede3_sha", false);
user_pref("security.ssl3.ecdh_rsa_des_ede3_sha",	 false);
user_pref("security.ssl3.ecdhe_ecdsa_des_ede3_sha",	 false);
user_pref("security.ssl3.ecdhe_rsa_des_ede3_sha",	 false);
user_pref("security.ssl3.rsa_des_ede3_sha",	 false);
user_pref("security.ssl3.rsa_fips_des_ede3_sha",		false);
user_pref("security.ssl3.ecdh_rsa_aes_256_sha",		 false);
user_pref("security.ssl3.ecdh_ecdsa_aes_256_sha",	 false);
user_pref("security.ssl3.rsa_camellia_256_sha", false);
user_pref("security.ssl3.ecdhe_rsa_aes_256_sha",	 true);
user_pref("security.ssl3.ecdhe_ecdsa_aes_256_sha",	 true);
user_pref("security.ssl3.ecdhe_ecdsa_aes_128_gcm_sha256",	true);
user_pref("security.ssl3.ecdhe_rsa_aes_128_gcm_sha256", true);
user_pref("security.ssl3.dhe_rsa_camellia_256_sha",	 false);
user_pref("security.ssl3.dhe_rsa_aes_256_sha",	 false);
user_pref("security.ssl3.dhe_dss_aes_128_sha",	 false);
user_pref("security.ssl3.dhe_dss_aes_256_sha",	 false);
user_pref("security.ssl3.dhe_dss_camellia_128_sha", false);
user_pref("security.ssl3.dhe_dss_camellia_256_sha",	 false);
user_pref("security.ssl3.rsa_aes_256_sha",	 true);
user_pref("security.ssl3.rsa_aes_128_sha", 	 true);
// browser switches //
// Preference name Value //
user_pref("browser.usedOnWindows10", false);
user_pref("browser.usedOnWindows10.introURL", "");
user_pref("browser.search.countryCode", "US");
user_pref("browser.search.region", "US");
user_pref("browser.download.manager.addToRecentDocs", false);
user_pref("browser.cache.disk.enable", false);
user_pref("browser.cache.disk_cache_ssl", false);
user_pref("browser.cache.memory.enable", false);
user_pref("browser.history_expire_visits", 0);
user_pref("browser.sessionstore.privacy_level",		 2);
user_pref("browser.helperApps.deleteTempFileOnExit",	 true);
user_pref("browser.pagethumbnails.capturing_disabled", true);
user_pref("browser.download.useDownloadDir",		 false);
user_pref("browser.sessionstore.postdata", 0);
user_pref("browser.sessionstore.enabled", false);
user_pref("browser.cache.offline.enable", false);
user_pref("browser.aboutHomeSnippets.updateUrl",	 "");
user_pref("browser.search.update",	 false);
user_pref("browser.search.suggest.enabled", false);
user_pref("browser.urlbar.suggest.searches", 	 false);
user_pref("browser.casting.enabled",		 false);
user_pref("browser.search.geoip.url",	 "");
user_pref("browser.newtabpage.enhanced",	 false);
user_pref("browser.newtab.preload",	 false);
user_pref("browser.newtabpage.directory.ping", "");
user_pref("browser.newtabpage.directory.source", "data:text/plain,{}");
user_pref("browser.selfsupport.url", "");
user_pref("browser.safebrowsing.enabled", false);
user_pref("browser.safebrowsing.malware.enabled", false);
user_pref("browser.safebrowsing.downloads.remote.enabled", false);
user_pref("browser.safebrowsing.reportMalwareMistakeURL", "");
user_pref("browser.safebrowsing.reportPhishMistakeURL", "");
user_pref("browser.safebrowsing.reportPhishURL", "");
user_pref("browser.safebrowsing.provider.google.appRepURL", "");
user_pref("browser.safebrowsing.provider.google.gethashURL", "");
user_pref("browser.safebrowsing.provider.google.reportURL", "");
user_pref("browser.safebrowsing.provider.google.updateURL", "");
user_pref("browser.safebrowsing.provider.mozilla.gethashURL", "");
user_pref("browser.safebrowsing.provider.mozilla.updateURL", "");
user_pref("browser.safebrowsing.downloads.enabled", false);
user_pref("browser.safebrowsing.downloads.remote.enabled", false);
user_pref("browser.display.use_document_fonts",	 0);
user_pref("browser.urlbar.filter.javascript",	 true);
user_pref("browser.send_pings", false);
user_pref("browser.send_pings.require_same_host",	 true);
user_pref("browser.fixup.alternate.enabled", false);
user_pref("browser.aboutHomeSnippets.updateUrl", "https://127.0.0.1");
user_pref("browser.eme.ui.enabled", false);
user_pref("browser.download.manager.addToRecentDocs", false); 
user_pref("browser.pagethumbnails.capturing_disabled", true);
user_pref("browser.pagethumbnails.storage_version", 3);
user_pref("browser.casting.enabled", false);
user_pref("browser.sessionhistory.max_entries", 2);
user_pref("browser.link.open_newwindow.restriction", 0);
user_pref("browser.search.geoSpecificDefaults", false);
user_pref("browser.trackingprotection.gethashURL", "");
user_pref("browser.trackingprotection.getupdateURL", "");
user_pref("browser.search.param.yahoo-fr", "");
user_pref("browser.search.param.yahoo-fr-ja", "");
// font switches //
// Preference name Value //
user_pref("font.name.serif.x-unicode", "Georgia");
user_pref("font.name.serif.x-western", "Georgia"); 
user_pref("font.name.sans-serif.x-unicode", "Arial");
user_pref("font.name.sans-serif.x-western", "Arial"); 
user_pref("font.name.monospace.x-unicode", "Lucida Console");
user_pref("font.name.monospace.x-western", "Lucida Console"); 
// privacy switches //
// Preference name Value //
user_pref("privacy.donottrackheader.enabled", true);
user_pref("privacy.donottrackheader.value", 1); 
user_pref("privacy.trackingprotection.enabled", true);
user_pref("privacy.trackingprotection.pbmode.enabled", false);
// webgl switches //
// Preference name Value //
user_pref("webgl.disabled", true);
user_pref("webgl.min_capability_mode", true);
user_pref("webgl.disable-extensions", true);
// gfx switches //
// Preference name Value //
user_pref("gfx.font_rendering.opentype_svg.enabled", false);
user_pref("gfx.downloadable_fonts.enabled", true);
user_pref("gfx.layerscope.enabled", false);
user_pref("gfx.direct2d.disabled", true);
// app switches //
user_pref("app.update.enabled", false);
user_pref("app.update.auto", false);
user_pref("app.update.disable_button.showUpdateHistory", false);
user_pref("app.update.service.enabled", false);
user_pref("app.update.showInstalledUI", true);
user_pref("app.update.silent", false);
user_pref("app.update.staging.enabled", false);
// etc switches //
// Preference name Value //
user_pref("loop.enabled", false);
user_pref("loop.server", "");
user_pref("loop.logDomains", false);
user_pref("gmp-eme-adobe.enabled", false);
user_pref("middlemouse.contentLoadURL", false);
user_pref("clipboard.autocopy", false);
user_pref("keyword.enabled",		 false);
user_pref("general.buildID.override",		 "20100101");
user_pref("pdfjs.disabled", true);
user_pref("pdfjs.enableWebGL", false);
user_pref("layout.css.visited_links_enabled", false);
user_pref("breakpad.reportURL", "");
user_pref("pageThumbs.enabled", false);
user_pref("beacon.enabled", false);
user_pref("layers.acceleration.disabled", true);

Answer 1

A few things:

• // comments don't need another // at the end, but you can leave it there if you want.
• You don't need to repeat // Preference name and value // before every block of prefs; just one at the start should do.
• Version control. Using git will help you keep track of the changes you've made.
• You have a duplicate dom.webnotifications.enabled.
• You might want to put a comment next to each pref to say what each one does.

• You could restructure your code as:

  const prefs = {
   'browser.something': true,
   'browser.somehing_else': false,
   // etc.
  }
  for (let pref in prefs) {
   user_pref(pref, prefs[pref])
  }
  

  if you plan on later making it more complex, but the code's clear enough as it is.

And some comments about the prefs you're modifying:

• Disabling Firefox auto-update. Bad idea. New versions won't make it any less secure, and always contain security fixes. You can use an extended support release if you don't like updating; ESRs get security fixes every few weeks but only get new features / performance improvements etc. every year.
• Disabling JavaScript. Do it if you want, but it's better to use an addon like NoScript which gives you more control.
• Disabling notifications. It won't really improve security: sites have to ask for permission before being allowed to send you notifications.
• And lastly, just be careful. These prefs can nuke your browser if you press the wrong button :)

• blacklight: about the auto update: this was one of the mistakes I overlooked (which is the reason I wanted the code to be checked) and i will fix this. About the javascript: i have chosen to turn it off because javascript is one of the most targeted platforms for malware, and even thoguh you are right about no script, it just feels wrong to leave java script turned on when making a security/privacy userscript. furthermore i have turned on notifications since in recent devlopments, notifications are used to insert malware into peoples computers. anyway thank you for reviewing. :)
• blacklight: (btw i am indeed trying to watch out with which prefs i use since you can break your browser with it. This is also one of the reasons i let the code be reviewed :)