Tails notes

Hardening tor browser in Tails

Create the user.js file:

nano /home/amnesia/.tor-browser/profile.default/user.js

Paste in the following:

user_pref("privacy.sanitize.sanitizeOnShutdown", true);
user_pref("javascript.enabled", false);
user_pref("network.cookie.lifetimePolicy", 2);
user_pref("dom.storage_access.enabled", false);
user_pref("dom.event.clipboardevents.enabled", false);
user_pref("geo.enabled", false);
user_pref("privacy.firstparty.isolate.block_post_message", true);
user_pref("privacy.resistFingerprinting.letterboxing", true);
user_pref("webgl.disabled", true);
user_pref("webgl.enable-webgl2", false);
user_pref("media.peerconnection.enabled", false);
user_pref("dom.enable_performance", false);
user_pref("gfx.webrender.all", false);
user_pref("privacy.resistFingerprinting.block_mozAddonManager", true);
user_pref("network.cookie.lifetimePolicy", 2);
user_pref("network.cookie.thirdparty.sessionOnly", true);
user_pref("browser.sessionstore.privacy_level", 2);
user_pref("network.http.referer.spoofSource", true);
user_pref("network.http.sendSecureXSiteReferrer", false);
user_pref("network.dns.disablePrefetch", true);
user_pref("network.predictor.enabled", false);
user_pref("network.http.referer.hideOnionSource", true);
user_pref("gfx.font_rendering.graphite.enabled", false);
user_pref("layout.css.font-visibility.level", 3);
user_pref("network.http.referer.trimmingPolicy", 2);
user_pref("network.http.referer.XOriginPolicy", 2);
user_pref("network.http.referer.XOriginTrimmingPolicy", 2);
user_pref("privacy.resistFingerprinting.reduceTimerPrecision", true);
user_pref("privacy.resistFingerprinting.reduceTimerPrecision.microseconds", 10000);
user_pref("fission.autostart", true);
user_pref("privacy.firstparty.isolate", true);
user_pref("privacy.trackingprotection.fingerprinting.enabled", true);
user_pref("privacy.trackingprotection.cryptomining.enabled", true);
user_pref("dom.webaudio.enabled", false);
user_pref("media.eme.enabled", false);
user_pref("media.video_stats.enabled", false);
user_pref("browser.startup.blankWindow", true);
user_pref("browser.download.start_downloads_in_tmp_dir", true);
user_pref("browser.helperApps.deleteTempFileOnExit", true);
user_pref("network.dns.blockDotOnion", false);
user_pref("network.proxy.socks_remote_dns", true);
user_pref("network.http.http3.enabled", false);
user_pref("dom.push.enabled", false);
user_pref("privacy.trackingprotection.enabled", true);
user_pref("privacy.trackingprotection.socialtracking.enabled", true);
user_pref("privacy.annotate_channels.strict_list.enabled", true);
user_pref("browser.send_pings", false);
user_pref("browser.display.use_document_fonts", 0);
user_pref("pdfjs.enabled", true);
user_pref("extensions.pocket.enabled", false);
user_pref("browser.safebrowsing.malware.enabled", false);
user_pref("browser.safebrowsing.phishing.enabled", false);
user_pref("webgl.enable-debug-renderer-info", false);
user_pref("media.navigator.enabled", false);
user_pref("dom.battery.enabled", false);
user_pref("device.sensors.enabled", false);
user_pref("accessibility.force_disabled", 1);
user_pref("browser.cache.offline.enable", false);
user_pref("beacon.enabled", false);
user_pref("clipboard.plainTextOnly", true);
user_pref("extensions.torbutton.use_nontor_proxy", false);
user_pref("extensions.torbutton.block_disk", true);
user_pref("dom.security.https_only_mode", true);
user_pref("dom.security.https_only_mode.upgrade_local", true);
user_pref("security.mixed_content.block_active_content", true);
user_pref("webspeech.recognition.enable", false);
user_pref("webspeech.synth.enabled", false);
user_pref("media.hardwaremediakeys.enabled", false);
user_pref("device.sensors.motion.enabled", false);
user_pref("device.sensors.orientation.enabled", false);
user_pref("dom.gamepad.enabled", false);
user_pref("browser.urlbar.suggest.searches", false);
user_pref("media.gmp-gmpopenh264.enabled", false);
user_pref("media.gmp-widevinecdm.enabled", false);
user_pref("browser.helperApps.neverAsk.saveToDisk", "application/pdf,application/octet-stream,application/zip");

Restart / start tor browser