This is difference between the default preference of Firefox 132.0 beta 9 and one of 131.0.3. This diff table is generated with my small script firefox-prefjs-surveyer.

Preference difference
PrefFirefox 130.0.1Firefox 131.0 beta 9
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.contentblocking.features.strict tp,tpPrivate,cookieBehavior5,cookieBehaviorPBM5,cm,fp,stp,emailTP,emailTPPrivate,lvl2,rp,rpTop,ocsp,qps,qpsPBM,fpp,fppPrivate tp,tpPrivate,cookieBehavior5,cookieBehaviorPBM5,cm,fp,stp,emailTP,emailTPPrivate,lvl2,rp,rpTop,ocsp,qps,qpsPBM,fpp,fppPrivate,3pcd
browser.firefox-view.max-history-rows 300 0
browser.newtabpage.activity-stream.default.sites https://www.youtube.com/,https://www.facebook.com/,https://www.wikipedia.org/,https://www.reddit.com/,https://www.amazon.com/,https://twitter.com/ https://www.youtube.com/,https://www.facebook.com/,https://www.wikipedia.org/,https://www.reddit.com/,https://twitter.com/
browser.newtabpage.activity-stream.discoverystream.contextualContent.enabled undefined false
browser.newtabpage.activity-stream.discoverystream.contextualContent.feeds undefined need_to_know
browser.newtabpage.activity-stream.discoverystream.contextualContent.listFeedTitle undefined
browser.newtabpage.activity-stream.discoverystream.contextualContent.locale-content-config undefined en-US,en-GB,en-CA,de
browser.newtabpage.activity-stream.discoverystream.contextualContent.region-content-config undefined
browser.newtabpage.activity-stream.discoverystream.contextualContent.selectedFeed undefined need_to_know
browser.newtabpage.activity-stream.discoverystream.endpoints https://getpocket.cdn.mozilla.net/,https://firefox-api-proxy.cdn.mozilla.net/,https://spocs.getpocket.com/,https://merino.services.mozilla.com/ https://getpocket.cdn.mozilla.net/,https://firefox-api-proxy.cdn.mozilla.net/,https://spocs.getpocket.com/,https://merino.services.mozilla.com/,https://ads.mozilla.org/
browser.newtabpage.activity-stream.discoverystream.placements.spocs undefined newtab_spocs
browser.newtabpage.activity-stream.discoverystream.placements.spocs.counts undefined 6
browser.newtabpage.activity-stream.discoverystream.placements.tiles undefined newtab_tile_1, newtab_tile_2, newtab_tile_3
browser.newtabpage.activity-stream.discoverystream.placements.tiles.counts undefined 1, 1, 1
browser.newtabpage.activity-stream.discoverystream.topicLabels.region-topic-label-config US, CA
browser.newtabpage.activity-stream.support.url https://support.mozilla.org/1/firefox/131.0.3/Linux/en-US/new-tab https://support.mozilla.org/1/firefox/132.0/Linux/en-US/new-tab
browser.newtabpage.activity-stream.unifiedAds.blockedAds undefined
browser.newtabpage.activity-stream.unifiedAds.endpoint undefined https://ads.mozilla.org/
browser.newtabpage.activity-stream.unifiedAds.spocs.enabled undefined false
browser.newtabpage.activity-stream.unifiedAds.tiles.enabled undefined false
browser.search.serpEventTelemetryCategorization.enabled false true
browser.shopping.experience2023.integratedSidebar undefined false
browser.tabs.groups.enabled undefined false
browser.urlbar.quicksuggest.exposureSuggestionTypes undefined
browser.urlbar.quicksuggest.hideSettingsUI undefined false
browser.urlbar.quicksuggest.shouldShowOnboardingDialog true false
browser.urlbar.weather.ignoreVPN false undefined
devtools.debugger.javascript-tracing-log-method console debugger-sidebar
devtools.debugger.javascript-tracing-max-depth 200 undefined
dom.closewatcher.enabled undefined false
dom.cookieStore.enabled undefined false
dom.element.contenteditable.plaintext-only.enabled undefined false
dom.fetchKeepalive.request_limit_per_origin 10 30
dom.fetchKeepalive.total_request_limit 30 100
dom.iframe_lazy_loading.enabled true undefined
dom.interactive_widget_default_resizes_visual false true
dom.ipc.processReuse.unusedGraceMs undefined 0
dom.mutation_events.enabled undefined true
dom.mutation_events.forceEnable undefined
dom.navigation.locationChangeRateLimit.count 200 undefined
dom.navigation.locationChangeRateLimit.timespan 10 undefined
dom.navigation.navigationRateLimit.count undefined 200
dom.navigation.navigationRateLimit.timespan undefined 10
dom.quotaManager.storageInitialization.pauseOnIOThreadMs undefined 0
dom.streams.from.enabled true undefined
dom.testing.sync-content-blocking-notifications false undefined
dom.viewTransitions.timeout-ms undefined 10000
dom.webnotifications.silent.enabled false true
dom.window.clientinformation.enabled true undefined
dom.window.sizeToContent.enabled false undefined
dom.worker.use_medium_high_event_queue true undefined
dom.workers.modules.enabled true undefined
extensions.formautofill.heuristics.autofillSameOriginWithTop undefined true
extensions.webcompat-reporter.enabled false true
gfx.webrender.debug.picture-borders undefined false
gfx.webrender.svg-filter-effects false true
gfx.webrender.svg-filter-effects.feoffset false true
input_event_queue.supported true undefined
javascript.options.experimental.json_parse_with_source undefined true
javascript.options.experimental.regexp_modifiers undefined true
javascript.options.mem.gc_max_empty_chunk_count 30 undefined
javascript.options.wasm_experimental_callRef_inlining undefined true
javascript.options.wasm_experimental_direct_inlining undefined true
javascript.options.wasm_experimental_inline_depth_limit 2 undefined
javascript.options.wasm_experimental_inline_size_limit 256 undefined
javascript.options.wasm_experimental_inlining_level undefined 5
javascript.options.wasm_experimental_tiering_level undefined 5
layers.child-process-shutdown true undefined
layout.css.forced-color-adjust.enabled true undefined
layout.css.forced-colors.enabled true undefined
layout.css.moz-user-modify.enabled undefined false
layout.css.prefers-contrast.enabled true undefined
media.devices.enumerate.legacy.allowlist undefined slack.com,*.slack.com
media.devices.enumerate.legacy.enabled true false
media.ffmpeg.encoder.enabled false true
media.rvfc.enabled false true
network.cookie.CHIPS.enabled true false
network.cookie.maxageCap undefined 34560000
network.cookie.useServerTime undefined false
network.fetchpriority.adjustments.images.low 0 10
network.fetchpriority.enabled false true
network.http.accept_include_images undefined false
network.http.http2.allow-push true false
network.http.http2.enabled.deps true false
network.http.http2.push_priority_update undefined false
network.http.http2.send-push-max-concurrent-frame undefined false
network.http.http2.send_NO_RFC7540_PRI undefined true
network.http.http3.ecn undefined false
network.http.largeKeepaliveFactor 10 20
network.http.referer.hideOnionSource false true
network.http.reject_NULs_in_response_header_values true undefined
network.http.strict_response_status_line_parsing true undefined
network.http.tailing.urgency undefined 6
network.http.useragent.freezeCpu true undefined
network.trr.max-retry-timeout-ms undefined 64000
network.url.strict_protocol_setter true undefined
network.websocket.extensions.permessage-deflate true undefined
pdfjs.enableHighlightEditor true undefined
permissions.media.query.enabled false true
privacy.documentCookies.maxage 0 undefined
privacy.query_stripping.strip_on_share.canDisable undefined true
privacy.restrict3rdpartystorage.heuristic.redirect true false
remote.retry-on-abort undefined true
security.app_menu.recordEventTelemetry true undefined
security.pki.cert_signature_cache_size undefined 128
security.pki.sct_signature_cache_size undefined 256
security.pki.use_modern_crypto_with_pkcs12 undefined true
security.sandbox.content.tempDirSuffix undefined
security.tls.enable_certificate_compression_brotli false true
security.tls.enable_certificate_compression_zlib false true
security.tls.enable_certificate_compression_zstd false true
security.tls.enable_kyber false true
sidebar.animation.duration-ms undefined 200
sidebar.animation.enabled undefined true
threads.control_event_queue.enabled true undefined
toolkit.backgroundtasks.tests.browserPrefsInherited undefined 15
toolkit.backgroundtasks.tests.browserPrefsOverriden undefined 16
toolkit.backgroundtasks.tests.geckoPrefsInherited undefined 17
toolkit.backgroundtasks.tests.geckoPrefsOverriden undefined 18
toolkit.telemetry.enabled false true
webchannel.allowObject.urlWhitelist https://content.cdn.mozilla.net https://install.mozilla.org undefined
webgl.colorspaces.prototype false undefined
webgl.drawing_buffer_color_space undefined true