This article shows the difference between the default preferences of Firefox 154.0 beta 8 and Firefox 153.0.3. The diff table below is generated using my small script firefox-prefjs-surveyer.

Preference difference
PrefFirefox 153.0.3Firefox 154.0 beta 8
app.releaseNotesURL https://www.firefox.com/%LOCALE%/firefox/%VERSION%/releasenotes/?utm_source=firefox-browser&utm_medium=firefox-desktop&utm_campaign=whatsnew https://www.firefox.com/%LOCALE%/firefox/%VERSION%beta/releasenotes/?utm_source=firefox-browser&utm_medium=firefox-desktop&utm_campaign=whatsnew
app.releaseNotesURL.aboutDialog https://www.firefox.com/%LOCALE%/firefox/%VERSION%/releasenotes/?utm_source=firefox-browser&utm_medium=firefox-desktop&utm_campaign=about-dialog https://www.firefox.com/%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.aboutwelcome.experimentsGate.enabled undefined true
browser.bypassAutoTriggerActions undefined false
browser.cache.disk.index.max_dump_interval_ms undefined 60000
browser.compactmode.auto.threshold undefined 0.05
browser.contentanalysis.use_wasm_backend undefined false
browser.contentanalysis.wasm_module_extension_require_signature undefined true
browser.ipProtection.fxa.useActivateFlow true undefined
browser.ml.pageExtractor.headlessTimeoutMs undefined 15000
browser.newtabpage.activity-stream.discoverystream.sections.contextualAds.region-config US
browser.newtabpage.activity-stream.feeds.pictureofthedayfeed undefined true
browser.newtabpage.activity-stream.feeds.privacyfeed undefined true
browser.newtabpage.activity-stream.feeds.stocksfeed undefined true
browser.newtabpage.activity-stream.feeds.webnotificationsfeed undefined false
browser.newtabpage.activity-stream.privacyInfo.url https://support.mozilla.org/1/firefox/153.0.3/Linux/en-US/sponsor-privacy https://support.mozilla.org/1/firefox/154.0/Linux/en-US/sponsor-privacy
browser.newtabpage.activity-stream.sectionsLearnMore.url https://support.mozilla.org/1/firefox/153.0.3/Linux/en-US/firefox-new-tab-personalization https://support.mozilla.org/1/firefox/154.0/Linux/en-US/firefox-new-tab-personalization
browser.newtabpage.activity-stream.support.url https://support.mozilla.org/1/firefox/153.0.3/Linux/en-US/new-tab https://support.mozilla.org/1/firefox/154.0/Linux/en-US/new-tab
browser.newtabpage.activity-stream.telemetry.ut.events false undefined
browser.newtabpage.activity-stream.topSitesGroupedPins undefined false
browser.newtabpage.activity-stream.unifiedAds.adsClient.enabled undefined false
browser.newtabpage.activity-stream.weather.hourlyEndpoint https://merino.services.mozilla.com/api/v1/weather/hourly-forecasts undefined
browser.newtabpage.activity-stream.weather.reportEndpoint https://merino.services.mozilla.com/api/v1/suggest undefined
browser.newtabpage.activity-stream.widgets.crossword.enabled undefined true
browser.newtabpage.activity-stream.widgets.crossword.endpoint undefined https://prod-games-particle.merino.prod.webservices.mozgcp.net/index.html
browser.newtabpage.activity-stream.widgets.crossword.interaction undefined false
browser.newtabpage.activity-stream.widgets.crossword.size undefined
browser.newtabpage.activity-stream.widgets.maximized true false
browser.newtabpage.activity-stream.widgets.pictureOfTheDay.dismissedDate undefined
browser.newtabpage.activity-stream.widgets.pictureOfTheDay.enabled undefined true
browser.newtabpage.activity-stream.widgets.pictureOfTheDay.endpoint undefined https://merino.services.mozilla.com/api/v1/rss/picture-of-the-day
browser.newtabpage.activity-stream.widgets.pictureOfTheDay.interaction undefined false
browser.newtabpage.activity-stream.widgets.pictureOfTheDay.setAsWallpaper.enabled undefined false
browser.newtabpage.activity-stream.widgets.pictureOfTheDay.size undefined
browser.newtabpage.activity-stream.widgets.pictureOfTheDay.wallpaperActive undefined
browser.newtabpage.activity-stream.widgets.privacy.enabled undefined true
browser.newtabpage.activity-stream.widgets.privacy.maxCount undefined 100
browser.newtabpage.activity-stream.widgets.privacy.size undefined
browser.newtabpage.activity-stream.widgets.stocks.enabled undefined true
browser.newtabpage.activity-stream.widgets.stocks.size undefined
browser.newtabpage.activity-stream.widgets.system.crossword.enabled undefined false
browser.newtabpage.activity-stream.widgets.system.maximized false true
browser.newtabpage.activity-stream.widgets.system.pictureOfTheDay.enabled undefined false
browser.newtabpage.activity-stream.widgets.system.privacy.enabled undefined false
browser.newtabpage.activity-stream.widgets.system.stocks.enabled undefined false
browser.preonboarding.enabled false undefined
browser.referrals.code undefined
browser.referrals.enabled undefined false
browser.shell.shortcut.test undefined false
browser.smartwindow.autoTabGrouping.enabled undefined false
browser.smartwindow.autoTabGrouping.loglevel undefined Warn
browser.smartwindow.autoTabGrouping.maxGroups undefined 3
browser.smartwindow.autoTabGrouping.minCandidateTabs undefined 4
browser.smartwindow.autoTabGrouping.minCohesion undefined 0.1
browser.smartwindow.autoTabGrouping.minTabsPerGroup undefined 2
browser.smartwindow.autoTabGrouping.timeoutMs undefined 8000
browser.smartwindow.mistralRelease undefined false
browser.tabs.contextmenu.altstructure.enabled undefined false
browser.tabs.selectMRUOnClose undefined false
browser.urlbar.ipc.chromeMessagePassing undefined false
clipboard.readCustomFormatsFromClipboard.enabled undefined false
devtools.browserconsole.filter.chrome undefined true
devtools.browserconsole.filter.content undefined true
devtools.netmonitor.bodyLimit undefined 1048576
devtools.netmonitor.requestBodyLimit 1048576 undefined
devtools.netmonitor.responseBodyLimit 1048576 undefined
devtools.performance.recording.duration.aboutlogging undefined 0
devtools.performance.recording.entries.aboutlogging undefined 10000000
devtools.performance.recording.features.aboutlogging undefined ["js","stackwalk","cpu","screenshots","memory"]
devtools.performance.recording.interval.aboutlogging undefined 1000
devtools.performance.recording.preset.aboutlogging undefined web-developer
devtools.performance.recording.threads.aboutlogging undefined ["GeckoMain","Compositor","Renderer"]
devtools.webconsole.filter.chrome undefined true
devtools.webconsole.filter.content undefined true
dom.audio_session.block_start_during_interrupt.enabled undefined false
dom.clipboard.customFormatSupport.enabled undefined false
dom.details_group.enabled true undefined
dom.document.name_getter_follow_spec.enabled true undefined
dom.document_language_metadata.load_timeout_ms undefined 4000
dom.document_language_metadata.max_retries undefined 3
dom.document_language_metadata.retry_delay_base_ms undefined 500
dom.editcontext.allow_canvas undefined false
dom.event.keypress.key.allow_lone_surrogate true false
dom.forms.datetime.timepicker false true
dom.forms.submit_async_navigation undefined true
dom.jsipc.check_safeForUntrustedWebProcess undefined true
dom.quotaManager.maxOriginsToSaveInOneBatch undefined 25
dom.quotaManager.originMetadataFlushCheckIntervalMs undefined 120000
dom.quotaManager.originWriteQuiescentThresholdMs undefined 300000
dom.serializer.includeCommonAncestor.enabled false undefined
dom.speculation_rules.enabled undefined false
dom.worker.remoteDebugger.enabled undefined false
extensions.formautofill.addresses.supported detect on
extensions.formautofill.useml false true
extensions.webcompat-reporter.enabled false true
general.autoscroll.speed_multiplier undefined 100
gfx.webrender.compositor false true
gfx.webrender.enable-angle undefined false
gl.allow-high-power undefined true
identity.fxaccounts.auth.useBearer undefined true
javascript.options.asmjs false undefined
javascript.options.experimental.iterator_chunking undefined true
javascript.options.experimental.iterator_includes undefined true
javascript.options.experimental.iterator_join undefined true
javascript.options.throw_on_asmjs_validation_failure false undefined
javascript.options.warn_asmjs_deprecation true undefined
layout.css.alpha-color-function.enabled undefined false
layout.css.anchor-positioning.position-try-order.enabled true undefined
layout.css.line-clamp.enabled undefined false
layout.css.margin-trim.enabled undefined false
layout.css.progress-function.enabled undefined false
layout.css.text-box.enabled false true
layout.css.text-decoration-inset-percentage.enabled undefined false
layout.css.tree-counting-functions.enabled false true
layout.css.typed-om-color.enabled undefined false
media.audio.reuse-stream-on-seek undefined false
media.geckoview.audio_session_type.enabled undefined false
media.seek-resume.audio-preroll-usecs undefined 100000
media.seek-resume.video-preroll-frames-hw undefined 1
media.seek-resume.video-preroll-frames-sw undefined 3
media.webrtc.hw.h264.enabled false true
network.cache.entry_wait_timeout_ms undefined 20000
network.cache.no_vary_search false true
network.dns.refresh_negative_addr_on_use undefined false
network.http.decode_content_for_known_compressed_extensions undefined true
network.http.happy_eyeballs_connection_attempt_delay 250 50
network.http.happy_eyeballs_connection_attempt_delay_multiplier undefined 2
network.http.happy_eyeballs_resolution_delay 50 25
network.http.happy_eyeballs_retry_without_trr undefined true
network.http.happy_eyeballs_upgrade_enabled undefined false
network.lna.websocket.enabled false true
network.mimesniff.sniff_misconfigured_types undefined true
network.sslkeylog_warning undefined true
pdfjs.enableSelectionRendering false true
pdfjs.enableSignatureVerification undefined false
permissions.desktop-notification.notNow.enabled false undefined
permissions.desktop-notification.telemetry.siteCategories {"facebook.com":"social","instagram.com":"social","twitter.com":"social","x.com":"social","tiktok.com":"social","linkedin.com":"social","reddit.com":"social","pinterest.com":"social","snapchat.com":"social","tumblr.com":"social","slack.com":"chat_communication","discord.com":"chat_communication","teams.microsoft.com":"chat_communication","zoom.us":"chat_communication","whatsapp.com":"chat_communication","telegram.org":"chat_communication","messenger.com":"chat_communication","skype.com":"chat_communication","signal.org":"chat_communication","viber.com":"chat_communication","mail.google.com":"email","gmail.com":"email","outlook.com":"email","outlook.live.com":"email","mail.yahoo.com":"email","yahoo.com":"email","protonmail.com":"email","aol.com":"email","icloud.com":"email","zoho.com":"email","youtube.com":"media_streaming","netflix.com":"media_streaming","twitch.tv":"media_streaming","hulu.com":"media_streaming","disneyplus.com":"media_streaming","hbomax.com":"media_streaming","primevideo.com":"media_streaming","crunchyroll.com":"media_streaming","paramountplus.com":"media_streaming","spotify.com":"media_streaming","soundcloud.com":"media_streaming","pandora.com":"media_streaming","tv.apple.com":"media_streaming","steampowered.com":"gaming","steamcommunity.com":"gaming","store.epicgames.com":"gaming","roblox.com":"gaming","playstation.com":"gaming","xbox.com":"gaming","nintendo.com":"gaming","battle.net":"gaming","itch.io":"gaming","chess.com":"gaming","calendar.google.com":"calendar","outlook.live.com":"calendar","calendar.yahoo.com":"calendar","calendar.com":"calendar","drive.google.com":"productivity_collaboration","docs.google.com":"productivity_collaboration","sheets.google.com":"productivity_collaboration","office.com":"productivity_collaboration","onedrive.live.com":"productivity_collaboration","dropbox.com":"productivity_collaboration","box.com":"productivity_collaboration","notion.so":"productivity_collaboration","trello.com":"productivity_collaboration","asana.com":"productivity_collaboration","monday.com":"productivity_collaboration","atlassian.com":"productivity_collaboration","gitlab.com":"productivity_collaboration","bitbucket.org":"productivity_collaboration","miro.com":"productivity_collaboration","figma.com":"productivity_collaboration","cnn.com":"news_publishers","nytimes.com":"news_publishers","bbc.com":"news_publishers","theguardian.com":"news_publishers","washingtonpost.com":"news_publishers","foxnews.com":"news_publishers","reuters.com":"news_publishers","apnews.com":"news_publishers","bloomberg.com":"news_publishers","wsj.com":"news_publishers","usatoday.com":"news_publishers","nbcnews.com":"news_publishers","abcnews.go.com":"news_publishers","cbsnews.com":"news_publishers","npr.org":"news_publishers","time.com":"news_publishers","newsweek.com":"news_publishers","politico.com":"news_publishers","huffpost.com":"news_publishers","buzzfeednews.com":"news_publishers"} undefined
places.semanticHistory.smartwindow.distanceThreshold undefined 0.6
privacy.trackingprotection.content.mirror.enabled undefined false
privacy.trackingprotection.urlclassifier.disable_for_channel_classifier undefined false
security.csp.truncate_blocked_uri_for_frame_navigations false undefined
security.ssl3.ecdhe_ecdsa_aes_256_sha true false
security.tls.enable_mlkem1024 undefined false
sidebar.openTabsPanel.collapsedWindows undefined {}
signon.rustMirror.collectFailedOrigins false undefined
signon.rustMirror.enabled false undefined
signon.storage.rust.active undefined false
signon.storage.rust.enabled undefined true
signon.storage.rust.migrationAttempts undefined 0
telemetry.fog.enable_fog_transport undefined false
toolkit.telemetry.enabled false true
toolkit.telemetry.site_categories undefined {"facebook.com":"social","instagram.com":"social","twitter.com":"social","x.com":"social","tiktok.com":"social","linkedin.com":"social","reddit.com":"social","pinterest.com":"social","snapchat.com":"social","tumblr.com":"social","slack.com":"chat_communication","discord.com":"chat_communication","teams.microsoft.com":"chat_communication","zoom.us":"chat_communication","whatsapp.com":"chat_communication","telegram.org":"chat_communication","messenger.com":"chat_communication","skype.com":"chat_communication","signal.org":"chat_communication","viber.com":"chat_communication","mail.google.com":"email","gmail.com":"email","outlook.com":"email","outlook.live.com":"email","mail.yahoo.com":"email","yahoo.com":"email","protonmail.com":"email","aol.com":"email","icloud.com":"email","zoho.com":"email","youtube.com":"media_streaming","netflix.com":"media_streaming","twitch.tv":"media_streaming","hulu.com":"media_streaming","disneyplus.com":"media_streaming","hbomax.com":"media_streaming","primevideo.com":"media_streaming","crunchyroll.com":"media_streaming","paramountplus.com":"media_streaming","spotify.com":"media_streaming","soundcloud.com":"media_streaming","pandora.com":"media_streaming","tv.apple.com":"media_streaming","steampowered.com":"gaming","steamcommunity.com":"gaming","store.epicgames.com":"gaming","roblox.com":"gaming","playstation.com":"gaming","xbox.com":"gaming","nintendo.com":"gaming","battle.net":"gaming","itch.io":"gaming","chess.com":"gaming","calendar.google.com":"calendar","outlook.live.com":"calendar","calendar.yahoo.com":"calendar","calendar.com":"calendar","drive.google.com":"productivity_collaboration","docs.google.com":"productivity_collaboration","sheets.google.com":"productivity_collaboration","office.com":"productivity_collaboration","onedrive.live.com":"productivity_collaboration","dropbox.com":"productivity_collaboration","box.com":"productivity_collaboration","notion.so":"productivity_collaboration","trello.com":"productivity_collaboration","asana.com":"productivity_collaboration","monday.com":"productivity_collaboration","atlassian.com":"productivity_collaboration","gitlab.com":"productivity_collaboration","bitbucket.org":"productivity_collaboration","miro.com":"productivity_collaboration","figma.com":"productivity_collaboration","cnn.com":"news_publishers","nytimes.com":"news_publishers","bbc.com":"news_publishers","theguardian.com":"news_publishers","washingtonpost.com":"news_publishers","foxnews.com":"news_publishers","reuters.com":"news_publishers","apnews.com":"news_publishers","bloomberg.com":"news_publishers","wsj.com":"news_publishers","usatoday.com":"news_publishers","nbcnews.com":"news_publishers","abcnews.go.com":"news_publishers","cbsnews.com":"news_publishers","npr.org":"news_publishers","time.com":"news_publishers","newsweek.com":"news_publishers","politico.com":"news_publishers","huffpost.com":"news_publishers","buzzfeednews.com":"news_publishers"}
webgl.disable-angle false true
widget.gtk.x11-key-repeat-throttle.enabled undefined false
widget.wayland.session-management.enabled undefined false