This article shows the difference between the default preferences of Firefox 145.0 beta 3 and Firefox 144.0. The diff table below is generated using my small script firefox-prefjs-surveyer.

Preference difference
PrefFirefox 145.0 beta 3Firefox 144.0
accessibility.uia.enable 0 2
app.normandy.test-prefs.bool undefined false
app.normandy.test-prefs.integer undefined 0
app.normandy.test-prefs.string undefined
app.releaseNotesURL https://www.mozilla.org/%LOCALE%/firefox/%VERSION%/releasenotes/?utm_source=firefox-browser&utm_medium=firefox-desktop&utm_campaign=whatsnew https://www.mozilla.org/%LOCALE%/firefox/%VERSION%beta/releasenotes/?utm_source=firefox-browser&utm_medium=firefox-desktop&utm_campaign=whatsnew
app.releaseNotesURL.aboutDialog https://www.mozilla.org/%LOCALE%/firefox/%VERSION%/releasenotes/?utm_source=firefox-browser&utm_medium=firefox-desktop&utm_campaign=about-dialog https://www.mozilla.org/%LOCALE%/firefox/%VERSION%beta/releasenotes/?utm_source=firefox-browser&utm_medium=firefox-desktop&utm_campaign=about-dialog
app.update.channel release beta
app.update.url.details https://www.mozilla.org/%LOCALE%/firefox/notes https://www.mozilla.org/%LOCALE%/firefox/beta/notes
app.update.url.manual https://www.mozilla.org/%LOCALE%/firefox/new?reason=manual-update https://www.mozilla.org/%LOCALE%/firefox/beta?reason=manual-update
browser.backup.backup-retry-limit undefined 100
browser.backup.disabled-on-idle-backup-retry undefined false
browser.backup.errorCode undefined 0
browser.backup.max-num-unremovable-staging-items undefined 5
browser.backup.template.fallback-download.aurora https://www.mozilla.org/firefox/channel/desktop/?utm_medium=firefox-desktop&utm_source=backup&utm_campaign=firefox-backup-2024&utm_content=control#developer https://www.firefox.com/channel/desktop/?utm_medium=firefox-desktop&utm_source=html-backup
browser.backup.template.fallback-download.beta https://www.mozilla.org/firefox/channel/desktop/?utm_medium=firefox-desktop&utm_source=backup&utm_campaign=firefox-backup-2024&utm_content=control#beta https://www.firefox.com/channel/desktop/?utm_medium=firefox-desktop&utm_source=html-backup
browser.backup.template.fallback-download.esr https://www.mozilla.org/firefox/enterprise/?utm_medium=firefox-desktop&utm_source=backup&utm_campaign=firefox-backup-2024&utm_content=control#download https://www.firefox.com/download/all/desktop-esr/?utm_medium=firefox-desktop&utm_source=html-backup
browser.backup.template.fallback-download.nightly https://www.mozilla.org/firefox/channel/desktop/?utm_medium=firefox-desktop&utm_source=backup&utm_campaign=firefox-backup-2024&utm_content=control#nightly https://www.firefox.com/channel/desktop/?utm_medium=firefox-desktop&utm_source=html-backup
browser.backup.template.fallback-download.release https://www.mozilla.org/firefox/download/thanks/?s=direct&utm_medium=firefox-desktop&utm_source=backup&utm_campaign=firefox-backup-2024&utm_content=control https://www.firefox.com/?utm_medium=firefox-desktop&utm_source=html-backup
browser.contextual-password-manager.enabled false true
browser.contextual-services.contextId.rotation-in-days 15 7
browser.ipProtection.domainExclusions undefined
browser.ipProtection.exceptionsMode undefined all
browser.ipProtection.userEnabled undefined false
browser.ml.smartAssist.apiKey undefined
browser.ml.smartAssist.enabled undefined false
browser.ml.smartAssist.endpoint undefined
browser.ml.smartAssist.model undefined
browser.ml.smartAssist.overrideNewTab undefined false
browser.newtabpage.activity-stream.discoverystream.optIn-region-weather-config undefined DE,GB,FR,ES,IT,CH,AT,BE,IE,NL,PL,CZ,SE,SG,HU,SK,FI,DK,NO,PT
browser.newtabpage.activity-stream.discoverystream.spocs.onDemand undefined false
browser.newtabpage.activity-stream.discoverystream.thumbsUpDown.region-thumbs-config US US, CA
browser.newtabpage.activity-stream.support.url https://support.mozilla.org/1/firefox/144.0/Linux/en-US/new-tab https://support.mozilla.org/1/firefox/145.0/Linux/en-US/new-tab
browser.newtabpage.activity-stream.system.showWeatherOptIn undefined false
browser.newtabpage.activity-stream.telemetry.ut.events false true
browser.newtabpage.activity-stream.weather.optInAccepted undefined false
browser.newtabpage.activity-stream.weather.optInDisplayed undefined false
browser.newtabpage.activity-stream.weather.staticData.enabled undefined false
browser.profiles.forceEnableRefresh undefined false
browser.safebrowsing.provider.google5.advisoryName undefined Google Safe Browsing
browser.safebrowsing.provider.google5.advisoryURL undefined https://developers.google.com/safe-browsing/v4/advisory
browser.safebrowsing.provider.google5.lists goog-phish-proto,googpub-phish-proto,goog-malware-proto,goog-unwanted-proto,goog-harmful-proto
browser.safebrowsing.provider.google5.reportMalwareMistakeURL undefined https://%LOCALE%.malware-error.mozilla.com/?url=
browser.safebrowsing.provider.google5.reportPhishMistakeURL undefined https://%LOCALE%.phish-error.mozilla.com/?url=
browser.safebrowsing.provider.google5.reportURL undefined https://safebrowsing.google.com/safebrowsing/diagnostic?site=
browser.search.visualSearch.featureGate false true
browser.sessionstore.log.appender.file.logOnSuccess false true
browser.sessionstore.logFlushIntervalSeconds undefined 3600
browser.sessionstore.loglevel Warn Debug
browser.settings-redesign.enabled undefined false
browser.tabs.groups.hoverPreview.enabled false true
browser.urlbar.lastUrlbarSearchSeconds undefined 0
browser.urlbar.trustPanel.featureGate undefined false
devtools.netmonitor.features.webtransport undefined false
dom.event.keypress.key.allow_lone_surrogate true false
dom.navigation.api.strict.enabled undefined false
dom.script_loader.experimental.navigation_cache undefined false
dom.script_loader.navigation_cache false undefined
dom.security.trusted_types.enabled false true
dom.security.unexpected_system_load_telemetry_enabled false true
dom.text_fragments.create_text_fragment.enabled false true
dom.webgpu.enabled false true
dom.webgpu.service-workers.enabled false true
dom.workers.throttling.enabled false true
extensions.cookie.rejectWhenInvalid false true
extensions.pocket.api api.getpocket.com undefined
extensions.pocket.bffApi firefox-api-proxy.cdn.mozilla.net undefined
extensions.pocket.bffRecentSaves true undefined
extensions.pocket.enabled false undefined
extensions.pocket.loggedOutVariant control undefined
extensions.pocket.oAuthConsumerKey 40249-e88c401e1b1f2242d9e441c4 undefined
extensions.pocket.oAuthConsumerKeyBff 94110-6d5ff7a89d72c869766af0e0 undefined
extensions.pocket.refresh.emailButton.enabled false undefined
extensions.pocket.showHome true undefined
extensions.pocket.site getpocket.com undefined
extensions.webcompat-reporter.enabled false true
gfx.webrender.precise-conic-gradients undefined false
gfx.webrender.precise-conic-gradients-swgl undefined false
gfx.webrender.precise-linear-gradients undefined false
gfx.webrender.precise-linear-gradients-swgl undefined false
gfx.webrender.precise-radial-gradients undefined true
gfx.webrender.precise-radial-gradients-swgl undefined true
javascript.options.atomics_wait_async false true
javascript.options.experimental.symbols_as_weakmap_keys undefined false
javascript.options.objectfuse_for_js_builtin_ctors_protos undefined true
javascript.options.use_js_microtask_queue undefined false
layers.gpu-process.allow-fallback-to-parent undefined true
layers.gpu-process.allow-software false true
layers.gpu-process.max_launch_attempts undefined 2
layers.gpu-process.stable.min-uptime-ms 240000 30000
layout.css.basic-shape-rect.enabled true undefined
layout.css.basic-shape-xywh.enabled true undefined
layout.css.grid-flex-spanning-items-intrinsic-sizing.enabled true undefined
layout.css.letter-spacing.model 0 2
layout.css.module-scripts.enabled undefined false
layout.css.outline-offset.snapping undefined 2
layout.css.overflow-clip-box.enabled false undefined
layout.css.text-autospace.enabled false true
layout.css.webkit-fill-available.all-size-properties.enabled undefined false
layout.css.webkit-fill-available.enabled false true
layout.dynamic-reflow-roots.enabled false true
mathml.font_family_math.enabled undefined false
media.mkv.enabled false true
media.webrtc.enable_pq_dtls false undefined
media.webrtc.enable_pq_hybrid_kex undefined true
media.webrtc.send_mlkem_keyshare undefined true
media.webrtc.simulcast.vp9.enabled false true
memory.phc.size_kb undefined 16384
network.auth.use_redirect_for_retries false true
network.http.accept-encoding.dictionary undefined dcb, dcz
network.http.dictionaries.enable undefined false
network.http.http3.ecn_mark false true
network.http.http3.inner_fallback_delay undefined 3000
network.http.http3.retry_different_ip_family false true
network.http.http3.use_nspr_for_io true false
network.http.idempotencyKey.enabled false true
network.http.retry_with_another_half_open false true
network.jar.record_failure_reason false true
network.lna.block_trackers false true
network.trr.async_connInfo false true
network.trr.idle_timeout_for_http3_conn 30 400
network.webtransport.datagram_size 1200 undefined
network.webtransport.datagrams.enabled true undefined
pdfjs.commentLearnMoreUrl undefined https://support.mozilla.org/%LOCALE%/kb/view-pdf-files-firefox-or-choose-another-viewer#w_add-a-comment-to-a-pdf
pdfjs.enableComment false true
pdfjs.enableHighlightFloatingButton false true
places.semanticHistory.featureGate false true
privacy.bounceTrackingProtection.requireStatefulBounces true false
privacy.wallet_schemes undefined openid4vp,mdoc,mdoc-openid4vp,haip,eudi-wallet,eudi-openid4vp,openid-credential-offer
reader.character_spacing 0 1
reader.word_spacing 0 1
security.disallow_non_local_systemprincipal_in_tests undefined false
security.integrity_policy.enabled false true
security.ssl3.ecdhe_ecdsa_aes_128_sha true false
security.ssl3.ecdhe_ecdsa_aes_256_sha true false
services.sync.engine.bookmarks.validation.enabled undefined true
services.sync.engine.passwords.validation.enabled undefined true
sidebar.animation.expand-on-hover.delay-duration-ms undefined 200
signon.rustMirror.enabled undefined false
toolkit.telemetry.enabled false true
ui.new-webcompat-reporter.send-more-info-link false true
ui.touch_hover.delay_ms undefined 100
widget.wayland.fractional-scale.enabled false true