Firefox user.js file I am using for privacy and performance (located at c:\Users\martin\AppData\Roaming\Mozilla\Firefox\Profiles or similar)

user.js

user_pref("browser.bookmarks.showMobileBookmarks", true);
user_pref("browser.ctrlTab.previews", true);
user_pref("browser.download.autohideButton", false);
user_pref("browser.download.panel.shown", true);
user_pref("browser.library.activity-stream.enabled", false);
user_pref("browser.newtabpage.activity-stream.feeds.places", true);
user_pref("browser.newtabpage.activity-stream.feeds.section.highlights", false);
user_pref("browser.newtabpage.activity-stream.feeds.telemetry", false);
user_pref("browser.newtabpage.activity-stream.filterAdult", false);
user_pref("browser.newtabpage.activity-stream.prerender", false);
user_pref("browser.newtabpage.activity-stream.showSponsored", false);
user_pref("browser.newtabpage.activity-stream.telemetry", false);
user_pref("browser.newtabpage.activity-stream.telemetry.ping.endpoint", "");
user_pref("browser.newtabpage.activity-stream.tippyTop.service.endpoint", "");
user_pref("browser.newtabpage.activity-stream.topSitesRows", 3);
user_pref("browser.newtabpage.enhanced", true);
user_pref("browser.ping-centre.telemetry", false);
user_pref("browser.safebrowsing.blockedURIs.enabled", false);
user_pref("browser.safebrowsing.downloads.enabled", false);
user_pref("browser.safebrowsing.downloads.remote.block_dangerous", false);
user_pref("browser.safebrowsing.downloads.remote.block_dangerous_host", false);
user_pref("browser.safebrowsing.downloads.remote.block_potentially_unwanted", false);
user_pref("browser.safebrowsing.downloads.remote.block_uncommon", false);
user_pref("browser.safebrowsing.downloads.remote.enabled", false);
user_pref("browser.safebrowsing.enabled", false);
user_pref("browser.safebrowsing.malware.enabled", false);
user_pref("browser.safebrowsing.phishing.enabled", false);
user_pref("browser.safebrowsing.provider.google.advisoryURL", "");
user_pref("browser.safebrowsing.provider.google.gethashURL", "");
user_pref("browser.safebrowsing.provider.google.lists", "");
user_pref("browser.safebrowsing.provider.google.pver", "");
user_pref("browser.safebrowsing.provider.google.reportMalwareMistakeURL", "");
user_pref("browser.safebrowsing.provider.google.reportPhishMistakeURL", "");
user_pref("browser.safebrowsing.provider.google.reportURL", "");
user_pref("browser.safebrowsing.provider.google.updateURL", "");
user_pref("browser.safebrowsing.provider.google4.advisoryName", "");
user_pref("browser.safebrowsing.provider.google4.advisoryURL", "");
user_pref("browser.safebrowsing.provider.google4.dataSharingURL", "");
user_pref("browser.safebrowsing.provider.google4.gethashURL", "");
user_pref("browser.safebrowsing.provider.google4.lastupdatetime", "");
user_pref("browser.safebrowsing.provider.google4.lists", "");
user_pref("browser.safebrowsing.provider.google4.nextupdatetime", "");
user_pref("browser.safebrowsing.provider.google4.pver", "");
user_pref("browser.safebrowsing.provider.google4.reportMalwareMistakeURL", "");
user_pref("browser.safebrowsing.provider.google4.reportPhishMistakeURL", "");
user_pref("browser.safebrowsing.provider.google4.reportURL", "");
user_pref("browser.safebrowsing.provider.google4.updateURL", "");
user_pref("browser.safebrowsing.provider.mozilla.gethashURL", "");
user_pref("browser.safebrowsing.provider.mozilla.lists", "");
user_pref("browser.safebrowsing.provider.mozilla.pver", "");
user_pref("browser.safebrowsing.provider.mozilla.updateURL", "");
user_pref("browser.search.countryCode", "GB");
user_pref("browser.search.geoSpecificDefaults", false);
user_pref("browser.search.geoSpecificDefaults.url", "");
user_pref("browser.search.geoip.url", "");
user_pref("browser.search.hiddenOneOffs", "Bing,Amazon.com,Twitter");
user_pref("browser.search.region", "GB");
user_pref("geo.wifi.uri", "");
user_pref("browser.tabs.loadInBackground", false);
user_pref("browser.tabs.tabMinWidth", 30);
user_pref("browser.tabs.warnOnClose", false);
user_pref("browser.urlbar.clickSelectsAll", true);
user_pref("browser.urlbar.maxRichResults", 15);
user_pref("browser.urlbar.trimURLs", false);
user_pref("datareporting.healthreport.uploadEnabled", false);
user_pref("datareporting.policy.dataSubmissionEnabled", false);
user_pref("datareporting.policy.firstRunURL", "");
user_pref("device.sensors.enabled", false);
user_pref("device.sensors.motion.enabled", false);
user_pref("device.sensors.orientation.enabled", false);
user_pref("devtools.aboutdebugging.showSystemAddons", true);
user_pref("devtools.onboarding.telemetry.logged", false);
user_pref("devtools.toolbox.splitconsoleEnabled", false);
user_pref("dom.push.enabled", false);
user_pref("permissions.default.desktop-notification", 2);
user_pref("permissions.default.geo", 2);
user_pref("experiments.activeExperiment", false);
user_pref("experiments.enabled", false);
user_pref("experiments.supported", false);
user_pref("extensions.pocket.enabled", false);
user_pref("extensions.ui.dictionary.hidden", false);
user_pref("extensions.ui.experiment.hidden", true);
user_pref("extensions.ui.locale.hidden", true);
user_pref("extensions.webextensions.remote", true);
user_pref("general.smoothScroll.durationToIntervalRatio", 1000);
user_pref("general.smoothScroll.lines.durationMaxMS", 100);
user_pref("general.smoothScroll.lines.durationMinMS", 100);
user_pref("general.smoothScroll.mouseWheel.durationMaxMS", 150);
user_pref("general.smoothScroll.mouseWheel.durationMinMS", 50);
user_pref("general.smoothScroll.other", false);
user_pref("general.smoothScroll.pixels", false);
user_pref("general.smoothScroll.scrollbars.durationMaxMS", 100);
user_pref("general.smoothScroll.scrollbars.durationMinMS", 100);
user_pref("general.warnOnAboutConfig", false);
user_pref("gfx.use_text_smoothing_setting", true);
user_pref("gfx.webrender.enabled", true);
user_pref("gfx.webrender.highlight-painted-layers", false);
user_pref("layers.acceleration.force-enabled", true);
user_pref("intl.accept_languages", "en-us,en,uk,ru");
user_pref("intl.locale.requested", "en-US");
user_pref("layout.css.devPixelsPerPx", "1.25");
user_pref("layout.css.osx-font-smoothing.enabled", true);
user_pref("layout.word_select.stop_at_punctuation", true);
user_pref("media.autoplay.enabled", false);
user_pref("media.av1.enabled", true);
user_pref("network.allow-experiments", false);
user_pref("network.cookie.prefsMigrated", true);
user_pref("network.dns.disablePrefetch", true);
user_pref("network.http.speculative-parallel-limit", 0);
user_pref("network.predictor.enabled", false);
user_pref("network.prefetch-next", false);
user_pref("network.security.esni.enabled", true);
user_pref("network.tcp.tcp_fastopen_enable", true);
user_pref("network.trr.mode", 2);
user_pref("network.trr.uri", "https://mozilla.cloudflare-dns.com/dns-query");
user_pref("network.warnOnAboutNetworking", false);
user_pref("privacy.donottrackheader.enabled", true);
user_pref("privacy.firstparty.isolate", true);
user_pref("privacy.resistFingerprinting", true);
user_pref("privacy.resistFingerprinting.autoDeclineNoUserInputCanvasPrompts", false);
user_pref("privacy.userContext.enabled", true);
user_pref("privacy.userContext.longPressBehavior", 2);
user_pref("privacy.userContext.ui.enabled", true);
user_pref("security.ssl.errorReporting.automatic", true);
user_pref("toolkit.identity.enabled", false);
user_pref("toolkit.telemetry.archive.enabled", false);
user_pref("toolkit.telemetry.bhrPing.enabled", false);
user_pref("toolkit.telemetry.coverage.opt-out", false);
user_pref("toolkit.telemetry.enabled", false);
user_pref("toolkit.telemetry.firstShutdownPing.enabled", false);
user_pref("toolkit.telemetry.hybridContent.enabled", false);
user_pref("toolkit.telemetry.infoURL", "");
user_pref("toolkit.telemetry.newProfilePing.enabled", false);
user_pref("toolkit.telemetry.reportingpolicy.firstRun", false);
user_pref("toolkit.telemetry.server", "");
user_pref("toolkit.telemetry.shutdownPingSender.enabled", false);
user_pref("toolkit.telemetry.unified", false);
user_pref("toolkit.telemetry.updatePing.enabled", false);