This is difference between the default preference of Firefox 55.0 beta 2 and one of 54.0.

Preference difference
PrefFirefox 54.0Firefox 55.0 beta 2
alerts.disableSlidingEffectfalseundefined
app.releaseNotesURLundefinedhttps://www.mozilla.org/%LOCALE%/firefox/%VERSION%/releasenotes/?utm_source=firefox-browser&utm_medium=firefox-browser&utm_campaign=whatsnew
app.update.badgefalseundefined
app.update.badgeWaitTime0345600
app.update.doorhangerundefinedtrue
app.update.download.promptMaxAttemptsundefined2
app.update.elevation.promptMaxAttemptsundefined2
app.update.link.updateAvailableWhatsNewundefinedupdate-available-whats-new
app.update.link.updateManualWhatsNewundefinedupdate-manual-whats-new
apz.allow_with_webrenderfalseundefined
apz.drag.enabledfalsetrue
apz.drag.initial.enabledundefinedtrue
browser.addon-watch.ignore["mochikit@mozilla.org","special-powers@mozilla.org","fxdevtools-adapters@mozilla.org","fx-devtools","webcompat-reporter@mozilla.org"]undefined
browser.addon-watch.interval-1undefined
browser.crashReports.unsubmittedCheck.enabledfalsetrue
browser.download.showPanelDropmarkerfalseundefined
browser.formautofill.enabledfalseundefined
browser.formautofill.experimentalfalseundefined
browser.formautofill.loglevelWarnundefined
browser.formfill.saveHttpsFormstrueundefined
browser.fullscreen.animatetrueundefined
browser.migrate.automigrate.enabledfalsetrue
browser.migrate.automigrate.inpage.ui.enabledundefinedfalse
browser.newtabpage.directory.pinghttps://tiles.services.mozilla.com/v3/links/undefined
browser.onboarding.enabledundefinedtrue
browser.photon.structure.enabledundefinedfalse
browser.preferences.defaultPerformanceSettings.enabledundefinedtrue
browser.preferences.offlineGroup.enabledundefinedtrue
browser.preferences.searchundefinedfalse
browser.preferences.useOldOrganizationundefinedtrue
browser.reader.detectedFirstArticlefalseundefined
browser.safebrowsing.provider.google4.updateURLhttps://safebrowsing.googleapis.com/v4/threatListUpdates:fetch?$ct=application/x-protobuf&key=%GOOGLE_API_KEY%https://safebrowsing.googleapis.com/v4/threatListUpdates:fetch?$ct=application/x-protobuf&key=%GOOGLE_API_KEY%&$httpMethod=POST
browser.safebrowsing.provider.mozilla.listsbase-track-digest256,mozstd-trackwhite-digest256,content-track-digest256,mozplugin-block-digest256,mozplugin2-block-digest256,block-flash-digest256,except-flash-digest256,allow-flashallow-digest256,except-flashallow-digest256,block-flashsubdoc-digest256,except-flashsubdoc-digest256base-track-digest256,mozstd-trackwhite-digest256,content-track-digest256,mozplugin-block-digest256,mozplugin2-block-digest256,block-flash-digest256,except-flash-digest256,allow-flashallow-digest256,except-flashallow-digest256,block-flashsubdoc-digest256,except-flashsubdoc-digest256,except-flashinfobar-digest256
browser.search.widget.inNavBarundefinedtrue
browser.selfsupport.urlhttps://self-repair.mozilla.org/%LOCALE%/repairundefined
browser.sessionstore.dom_storage_limitundefined2048
browser.sessionstore.idleDelayundefined180000
browser.sessionstore.interval.idleundefined3600000
browser.sessionstore.restore_tabs_lazilyundefinedtrue
browser.shell.didSkipDefaultBrowserCheckOnFirstRunundefinedfalse
browser.shell.skipDefaultBrowserChecktrueundefined
browser.shell.skipDefaultBrowserCheckOnFirstRunfalsetrue
browser.suppress_first_window_animationundefinedtrue
browser.tabs.animatetrueundefined
browser.tabs.remote.allowLinkedWebInFileUriProcessundefinedtrue
browser.tabs.remote.separateFileUriProcessfalsetrue
browser.uidensityundefined0
browser.urlbar.oneOffSearchesfalsetrue
browser.urlbar.suggest.searchesfalsetrue
browser.urlbar.timesBeforeHidingSuggestionsHintundefined4
datareporting.policy.firstRunURLhttps://www.mozilla.org/privacy/firefox/
devtools.computed.boxmodel.openedundefinedtrue
devtools.debugger.expressionsundefined[]
devtools.debugger.file-search-case-sensitiveundefinedtrue
devtools.debugger.file-search-regex-matchundefinedfalse
devtools.debugger.file-search-whole-wordundefinedfalse
devtools.debugger.ignore-caught-exceptionstruefalse
devtools.debugger.pending-breakpointsundefined[]
devtools.debugger.prefs-schema-versionundefined1.0.0
devtools.debugger.ui.framework-grouping-onundefinedtrue
devtools.devedition.promo.enabledfalsetrue
devtools.gridinspector.showGridAreasundefinedfalse
devtools.inspector.mdnDocsTooltip.enabledtruefalse
devtools.layout.boxmodel.openedundefinedtrue
devtools.layout.grid.openedundefinedtrue
devtools.netmonitor.hiddenColumnsundefined["cookies","duration","endTime","latency","protocol","remoteip","responseTime","scheme","setCookies","startTime"]
devtools.source-map.client-service.enabledundefinedtrue
devtools.source-map.locations.enabledfalseundefined
devtools.storage.enabledfalsetrue
devtools.webide.autosaveFilestrueundefined
devtools.webide.showProjectEditortrueundefined
devtools.webide.widget.autoinstalltrueundefined
devtools.webide.widget.enabledfalseundefined
devtools.webide.widget.inNavbarByDefaultfalseundefined
dom.IntersectionObserver.enabledfalsetrue
dom.allow_named_properties_object_for_xraysundefined1
dom.audiochannel.mutedByDefaultfalseundefined
dom.enable_user_timingtrueundefined
dom.forms.datetime.othersundefinedfalse
dom.forms.requestAutocompletefalseundefined
dom.gamepad.extensions.enabledfalsetrue
dom.input.skip_cursor_move_for_same_value_setundefinedtrue
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dom.ipc.plugins.asyncdrawing.enabledfalsetrue
dom.ipc.plugins.forcedirect.enabledundefinedtrue
dom.ipc.processCount.fileundefined1
dom.ipc.processPrelaunch.enabledundefinedtrue
dom.keyboardevent.code.enabledtrueundefined
dom.min_tracking_background_timeout_valueundefined10000
dom.min_tracking_timeout_valueundefined4
dom.mms.defaultServiceId0undefined
dom.mms.requestReadReporttrueundefined
dom.mms.requestStatusReporttrueundefined
dom.mms.retrievalRetryCount4undefined
dom.mms.retrievalRetryIntervals60000,300000,600000,1800000undefined
dom.mms.retrieval_modemanualundefined
dom.mms.sendRetryCount3undefined
dom.mms.sendRetryInterval10000,60000,180000undefined
dom.mms.version19undefined
dom.payments.request.enabledundefinedfalse
dom.popup_allowed_eventschange click dblclick mouseup notificationclick reset submit touchendchange click dblclick mouseup pointerup notificationclick reset submit touchend
dom.promise_rejection_events.enabledundefinedfalse
dom.requestIdleCallback.enabledfalsetrue
dom.script_loader.bytecode_cache.enabledundefinedfalse
dom.script_loader.bytecode_cache.strategyundefined0
dom.storageManager.prompt.testingundefinedfalse
dom.storageManager.prompt.testing.allowundefinedfalse
dom.timeout.max_consecutive_callbacks5undefined
dom.timeout.max_consecutive_callbacks_msundefined4
dom.timeout.tracking_throttling_delayundefined30000
dom.url.encode_decode_hashtrueundefined
dom.url.getters_decode_hashfalseundefined
dom.vr.autoactivate.enabledundefinedfalse
dom.vr.controller_trigger_thresholdundefined0.1
dom.vr.navigation.timeoutundefined5000
dom.vr.poseprediction.enabledfalsetrue
dom.vr.puppet.submitframeundefined0
dom.vr.require-gestureundefinedtrue
dom.xhr.lowercase_header.enabledundefinedfalse
editor.use_div_for_default_newlinesundefinedtrue
extensions.allow-non-mpc-extensionsundefinedtrue
extensions.dss.enabledfalseundefined
extensions.formautofill.addresses.enabledundefinedtrue
extensions.formautofill.experimentalundefinedfalse
extensions.formautofill.heuristics.enabledundefinedtrue
extensions.formautofill.loglevelundefinedWarn
extensions.geckoProfiler.acceptedExtensionIdsundefinedgeckoprofiler@mozilla.com,quantum-foxfooding@mozilla.com
extensions.geckoProfiler.getSymbolRulesundefinedlocalBreakpad,remoteBreakpad,nm
extensions.geckoProfiler.symbols.urlundefinedhttp://symbols.mozilla.org/
extensions.legacy.enabledundefinedtrue
extensions.legacy.exceptionsundefined{972ce4c6-7e08-4474-a285-3208198ce6fd},testpilot@cliqz.com,@testpilot-containers,jid1-NeEaf3sAHdKHPA@jetpack,@activity-streams,pulse@mozilla.com,@testpilot-addon,@min-vid,tabcentertest1@mozilla.com,snoozetabs@mozilla.com,speaktome@mozilla.com,hoverpad@mozilla.com
extensions.screenshots.disabledundefinedfalse
extensions.startupScanScopesundefined0
extensions.webextOptionalPermissionPromptsundefinedtrue
extensions.webextPermissionPromptsundefinedtrue
extensions.webextensions.themes.enabledfalsetrue
extensions.webextensions.themes.icons.buttonsundefinedback,forward,reload,stop,bookmark_star,bookmark_menu,downloads,home,app_menu,cut,copy,paste,new_window,new_private_window,save_page,print,history,full_screen,find,options,addons,developer,synced_tabs,open_file,sidebars,share_page,subscribe,text_encoding,email_link,forget,pocket
extensions.webextensions.themes.icons.enabledundefinedfalse
font.name-list.monospace.arundefinedmonospace
font.name-list.monospace.elundefinedmonospace
font.name-list.monospace.heundefinedmonospace
font.name-list.monospace.jaundefinedmonospace
font.name-list.monospace.koundefinedmonospace
font.name-list.monospace.thundefinedmonospace
font.name-list.monospace.x-armnundefinedmonospace
font.name-list.monospace.x-bengundefinedmonospace
font.name-list.monospace.x-cansundefinedmonospace
font.name-list.monospace.x-cyrillicundefinedmonospace
font.name-list.monospace.x-devanagariundefinedmonospace
font.name-list.monospace.x-ethiundefinedmonospace
font.name-list.monospace.x-georundefinedmonospace
font.name-list.monospace.x-gujrundefinedmonospace
font.name-list.monospace.x-guruundefinedmonospace
font.name-list.monospace.x-khmrundefinedmonospace
font.name-list.monospace.x-kndaundefinedmonospace
font.name-list.monospace.x-mathundefinedmonospace
font.name-list.monospace.x-mlymundefinedmonospace
font.name-list.monospace.x-oryaundefinedmonospace
font.name-list.monospace.x-sinhundefinedmonospace
font.name-list.monospace.x-tamilundefinedmonospace
font.name-list.monospace.x-teluundefinedmonospace
font.name-list.monospace.x-tibtundefinedmonospace
font.name-list.monospace.x-unicodeundefinedmonospace
font.name-list.monospace.x-westernundefinedmonospace
font.name-list.monospace.zh-CNundefinedmonospace
font.name-list.monospace.zh-HKundefinedmonospace
font.name-list.monospace.zh-TWundefinedmonospace
font.name-list.sans-serif.arundefinedsans-serif
font.name-list.sans-serif.elundefinedsans-serif
font.name-list.sans-serif.heundefinedsans-serif
font.name-list.sans-serif.jaundefinedsans-serif
font.name-list.sans-serif.koundefinedsans-serif
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font.name.cursive.arundefined
font.name.cursive.elundefined
font.name.cursive.heundefined
font.name.cursive.jaundefined
font.name.cursive.koundefined
font.name.cursive.thundefined
font.name.cursive.x-armnundefined
font.name.cursive.x-bengundefined
font.name.cursive.x-cansundefined
font.name.cursive.x-cyrillicundefined
font.name.cursive.x-devanagariundefined
font.name.cursive.x-ethiundefined
font.name.cursive.x-georundefined
font.name.cursive.x-gujrundefined
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font.name.cursive.x-khmrundefined
font.name.cursive.x-kndaundefined
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font.name.cursive.x-mlymundefined
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font.name.cursive.zh-HKundefined
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font.name.monospace.armonospace
font.name.monospace.elmonospace
font.name.monospace.hemonospace
font.name.monospace.jamonospace
font.name.monospace.komonospace
font.name.monospace.thmonospace
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font.name.sans-serif.elsans-serif
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font.name.sans-serif.x-kndasans-serif
font.name.sans-serif.x-mathsans-serif
font.name.sans-serif.x-mlymsans-serif
font.name.sans-serif.x-oryasans-serif
font.name.sans-serif.x-sinhsans-serif
font.name.sans-serif.x-tamilsans-serif
font.name.sans-serif.x-telusans-serif
font.name.sans-serif.x-tibtsans-serif
font.name.sans-serif.x-unicodesans-serif
font.name.sans-serif.x-westernsans-serif
font.name.sans-serif.zh-CNsans-serif
font.name.sans-serif.zh-HKsans-serif
font.name.sans-serif.zh-TWsans-serif
font.name.serif.arserif
font.name.serif.elserif
font.name.serif.heserif
font.name.serif.jaserif
font.name.serif.koserif
font.name.serif.thserif
font.name.serif.x-armnserif
font.name.serif.x-bengserif
font.name.serif.x-cansserif
font.name.serif.x-cyrillicserif
font.name.serif.x-devanagariserif
font.name.serif.x-ethiserif
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font.name.serif.x-gujrserif
font.name.serif.x-guruserif
font.name.serif.x-khmrserif
font.name.serif.x-kndaserif
font.name.serif.x-mathLatin Modern Math
font.name.serif.x-mlymserif
font.name.serif.x-oryaserif
font.name.serif.x-sinhserif
font.name.serif.x-tamilserif
font.name.serif.x-teluserif
font.name.serif.x-tibtserif
font.name.serif.x-unicodeserif
font.name.serif.x-westernserif
font.name.serif.zh-CNserif
font.name.serif.zh-HKserif
font.name.serif.zh-TWserif
font.size.systemFontScaleundefined100
geo.security.allowinsecuretrueundefined
geo.wifi.urihttps://www.googleapis.com/geolocation/v1/geolocate?key=%GOOGLE_API_KEY%https://location.services.mozilla.com/v1/geolocate?key=%MOZILLA_API_KEY%
gfx.font_rendering.fontconfig.fontlist.enabledtrueundefined
gfx.vr.openvr-runtimeundefined
gfx.webrender.enabledtruefalse
gfx.webrender.profiler.enabledundefinedfalse
gfx.webrendest.enabledundefinedfalse
identity.fxaccounts.profile_image.enabledtrueundefined
image.mem.animated.discardablefalsetrue
javascript.options.mem.gc_incremental_slice_ms105
javascript.options.shared_memoryfalsetrue
jsloader.reuseGlobalfalseundefined
layers.advanced.background-colorundefined2
layers.advanced.background-imageundefined2
layers.advanced.border-layersfalse2
layers.advanced.boxshadow-inset-layersundefined2
layers.advanced.boxshadow-outer-layersundefined2
layers.advanced.bullet-layersundefined2
layers.advanced.button-foreground-layersundefined2
layers.advanced.canvas-background-colorundefined2
layers.advanced.caret-layersfalse2
layers.advanced.columnRule-layersundefined2
layers.advanced.displaybuttonborder-layersundefined2
layers.advanced.filter-layersundefined2
layers.advanced.image-layersundefined2
layers.advanced.outline-layersundefined2
layers.advanced.solid-colorundefined2
layers.advanced.tableundefined2
layers.advanced.text-layersundefined2
layers.frame-counterfalseundefined
layers.geometry.d3d11.enabledundefinedtrue
layers.popups.compositing.enabledundefinedfalse
layout.accessiblecaret.timeout_ms0undefined
layout.css.background-clip-text.enabledtrueundefined
layout.css.column-span.enabledundefinedfalse
layout.css.display-flow-root.enabledtrueundefined
layout.css.float-logical-values.enabledfalsetrue
layout.css.servo.enabledundefinedfalse
layout.css.style-attr-with-xml-base.disabledundefinedtrue
layout.css.text-justify.enabledfalsetrue
layout.css.variables.enabledtrueundefined
layout.frame_rate.precisefalseundefined
lightweightThemes.recommendedThemes[{"id":"recommended-1","homepageURL":"https://addons.mozilla.org/firefox/addon/a-web-browser-renaissance/","headerURL":"resource:///chrome/browser/content/browser/defaultthemes/1.header.jpg","footerURL":"resource:///chrome/browser/content/browser/defaultthemes/1.footer.jpg","textcolor":"#000000","accentcolor":"#f2d9b1","iconURL":"resource:///chrome/browser/content/browser/defaultthemes/1.icon.jpg","previewURL":"resource:///chrome/browser/content/browser/defaultthemes/1.preview.jpg","author":"Sean.Martell","version":"0"},{"id":"recommended-2","homepageURL":"https://addons.mozilla.org/firefox/addon/space-fantasy/","headerURL":"resource:///chrome/browser/content/browser/defaultthemes/2.header.jpg","footerURL":"resource:///chrome/browser/content/browser/defaultthemes/2.footer.jpg","textcolor":"#ffffff","accentcolor":"#d9d9d9","iconURL":"resource:///chrome/browser/content/browser/defaultthemes/2.icon.jpg","previewURL":"resource:///chrome/browser/content/browser/defaultthemes/2.preview.jpg","author":"fx5800p","version":"1.0"},{"id":"recommended-4","homepageURL":"https://addons.mozilla.org/firefox/addon/pastel-gradient/","headerURL":"resource:///chrome/browser/content/browser/defaultthemes/4.header.png","footerURL":"resource:///chrome/browser/content/browser/defaultthemes/4.footer.png","textcolor":"#000000","accentcolor":"#000000","iconURL":"resource:///chrome/browser/content/browser/defaultthemes/4.icon.png","previewURL":"resource:///chrome/browser/content/browser/defaultthemes/4.preview.png","author":"darrinhenein","version":"1.0"}][{"id":"recommended-1","homepageURL":"https://addons.mozilla.org/firefox/addon/a-web-browser-renaissance/","headerURL":"resource:///chrome/browser/content/browser/defaultthemes/1.header.jpg","textcolor":"#000000","accentcolor":"#f2d9b1","iconURL":"resource:///chrome/browser/content/browser/defaultthemes/1.icon.jpg","previewURL":"resource:///chrome/browser/content/browser/defaultthemes/1.preview.jpg","author":"Sean.Martell","version":"0"},{"id":"recommended-2","homepageURL":"https://addons.mozilla.org/firefox/addon/space-fantasy/","headerURL":"resource:///chrome/browser/content/browser/defaultthemes/2.header.jpg","textcolor":"#ffffff","accentcolor":"#d9d9d9","iconURL":"resource:///chrome/browser/content/browser/defaultthemes/2.icon.jpg","previewURL":"resource:///chrome/browser/content/browser/defaultthemes/2.preview.jpg","author":"fx5800p","version":"1.0"},{"id":"recommended-4","homepageURL":"https://addons.mozilla.org/firefox/addon/pastel-gradient/","headerURL":"resource:///chrome/browser/content/browser/defaultthemes/4.header.png","textcolor":"#000000","accentcolor":"#000000","iconURL":"resource:///chrome/browser/content/browser/defaultthemes/4.icon.png","previewURL":"resource:///chrome/browser/content/browser/defaultthemes/4.preview.png","author":"darrinhenein","version":"1.0"}]
marionette.enabledfalseundefined
marionette.forcelocaltrueundefined
media.cache.resource-indexundefined8192
media.cache_readahead_limit99999960
media.cache_resume_threshold99999930
media.decoder-doctor.decode-errors-allowedundefinedNS_ERROR_DOM_MEDIA_DEMUXER_ERR, NS_ERROR_DOM_MEDIA_METADATA_ERR
media.decoder-doctor.decode-warnings-allowedundefinedNS_ERROR_DOM_MEDIA_DEMUXER_ERR, NS_ERROR_DOM_MEDIA_METADATA_ERR
media.decoder-doctor.new-issue-endpointundefinedhttps://webcompat.com/issues/new
media.eme.chromium-api.enabledundefinedtrue
media.eme.chromium-api.video-shmemsundefined4
media.playback.warnings-as-errorsundefinedfalse
media.suspend-bkgnd-video.enabledfalsetrue
media.throttle-factorundefined2
media.throttle-regardless-of-download-rateundefinedfalse
media.webvtt.pseudo.enabledundefinedtrue
mms.debugging.enabledfalseundefined
network.auth.subresource-img-cross-origin-http-auth-allowundefinedtrue
network.dns.forceResolveundefined
network.http.bypass-cachelock-threshold200000undefined
network.http.enablePerElementReferrertrueundefined
network.http.focused_window_transaction_ratioundefined0.9
network.http.max-urgent-start-excessive-connections-per-hostundefined3
network.http.originextensionundefinedtrue
network.http.rcwn.cache_queue_normal_thresholdundefined8
network.http.rcwn.cache_queue_priority_thresholdundefined2
network.http.rcwn.enabledundefinedfalse
network.http.rcwn.small_resource_size_kbundefined256
network.http.spdy.timeout180170
network.http.throttle.enableundefinedtrue
network.http.throttle.resume-background-inundefined1000
network.http.throttle.resume-forundefined100
network.http.throttle.suspend-forundefined900
network.jar.block-remote-filesfalsetrue
network.predictor.enable-prefetchfalsetrue
network.tcp.tcp_fastopen_consecutive_failure_limitundefined5
network.tcp.tcp_fastopen_enableundefinedfalse
network.throttle.enabletrueundefined
network.throttle.resume-for2000undefined
network.throttle.suspend-for2000undefined
pdfium.enabledundefinedfalse
plugins.favorfallback.modeneverfollow-ctp
plugins.favorfallback.rulesnosrc,video
plugins.flashBlock.enabledfalsetrue
plugins.http_https_onlyundefinedtrue
plugins.remember_infobar_dismissalundefinedtrue
plugins.show_infobarundefinedtrue
privacy.resistFingerprintingundefinedfalse
privacy.trackingprotection.annotate_channelsfalsetrue
ril.numRadioInterfaces0undefined
security.OCSP.timeoutMilliseconds.hardundefined10000
security.OCSP.timeoutMilliseconds.softundefined2000
security.allow_chrome_frames_inside_contentundefinedfalse
security.data_uri.inherit_security_contexttrueundefined
security.data_uri.unique_opaque_originundefinedfalse
security.insecure_field_warning.ignore_local_ip_addressundefinedtrue
security.tls.enable_0rtt_datafalsetrue
security.tls.version.max34
services.sync.maxResyncsundefined5
services.sync.prefs.sync.javascript.enabledtrueundefined
sidebar.position_startundefinedtrue
social.sidebar.unload_timeout_ms10000undefined
svg.context-properties.content.enabledundefinedfalse
svg.transform-box.enabledfalsetrue
toolkit.cosmeticAnimations.enabledundefinedtrue
toolkit.dump.emitundefinedfalse
toolkit.telemetry.newProfilePing.enabledundefinedtrue
toolkit.telemetry.shutdownPingSender.enabledundefinedtrue
urlclassifier.disallow_completionstest-malware-simple,test-phish-simple,test-unwanted-simple,test-track-simple,test-trackwhite-simple,test-block-simple,test-flashallow-simple,testexcept-flashallow-simple,test-flash-simple,testexcept-flash-simple,test-flashsubdoc-simple,testexcept-flashsubdoc-simple,goog-downloadwhite-digest256,base-track-digest256,mozstd-trackwhite-digest256,content-track-digest256,mozplugin-block-digest256,mozplugin2-block-digest256,block-flash-digest256,except-flash-digest256,allow-flashallow-digest256,except-flashallow-digest256,block-flashsubdoc-digest256,except-flashsubdoc-digest256test-malware-simple,test-phish-simple,test-unwanted-simple,test-track-simple,test-trackwhite-simple,test-block-simple,test-flashallow-simple,testexcept-flashallow-simple,test-flash-simple,testexcept-flash-simple,test-flashsubdoc-simple,testexcept-flashsubdoc-simple,goog-downloadwhite-digest256,base-track-digest256,mozstd-trackwhite-digest256,content-track-digest256,mozplugin-block-digest256,mozplugin2-block-digest256,block-flash-digest256,except-flash-digest256,allow-flashallow-digest256,except-flashallow-digest256,block-flashsubdoc-digest256,except-flashsubdoc-digest256,except-flashinfobar-digest256
urlclassifier.downloadAllowTablegoog-downloadwhite-digest256
urlclassifier.flashInfobarTableundefinedexcept-flashinfobar-digest256
urlclassifier.max-complete-age2700undefined
urlclassifier.update.response_timeout_msundefined15000
urlclassifier.update.timeout_msundefined60000
wap.UAProf.tagnamex-wap-profileundefined
wap.UAProf.urlundefined
webgl.force-index-validationundefinedfalse
webrender.highlight-painted-layersundefinedfalse
widget.chrome.allow-gtk-dark-themeundefinedfalse
widget.content.allow-gtk-dark-themeundefinedfalse
Default pref Javascript files
PrefFirefox 54.0Firefox 55.0 beta 2
browser/omni.ja.d/defaults/preferences/debugger.jsN/Apresent
browser/omni.ja.d/defaults/preferences/devtools.jspresentpresent
browser/omni.ja.d/defaults/preferences/firefox-branding.jspresentpresent
browser/omni.ja.d/defaults/preferences/firefox-l10n.jspresentpresent
browser/omni.ja.d/defaults/preferences/firefox.jspresentpresent
browser/omni.ja.d/defaults/preferences/webide-prefs.jspresentpresent
omni.ja.d/defaults/pref/marionette.jspresentpresent
omni.ja.d/defaults/pref/services-sync.jspresentpresent
omni.ja.d/greprefs.jspresentpresent