This is difference between the default preference of Firefox 133.0 beta 9 and one of 132.0.2. This diff table is generated with my small script firefox-prefjs-surveyer.

Preference difference
PrefFirefox 132.0.2Firefox 133.0 beta 9
accessibility.enable_all_cache_domains undefined false
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
apz.gtk.touchpad_hold.enabled undefined false
browser.contentblocking.features.strict tp,tpPrivate,cookieBehavior5,cookieBehaviorPBM5,cm,fp,stp,emailTP,emailTPPrivate,lvl2,rp,rpTop,ocsp,qps,qpsPBM,fpp,fppPrivate,3pcd tp,tpPrivate,cookieBehavior5,cookieBehaviorPBM5,cm,fp,stp,emailTP,emailTPPrivate,lvl2,rp,rpTop,ocsp,qps,qpsPBM,fpp,fppPrivate,3pcd,btp
browser.ml.chat.prompts.1 {"id":"simplify","l10nId":"genai-prompts-simplify"} {"id":"explain","l10nId":"genai-prompts-explain"}
browser.ml.chat.prompts.2 {"id":"quiz","l10nId":"genai-prompts-quiz","targeting":"!provider|regExpMatch('gemini')"} {"id":"simplify","l10nId":"genai-prompts-simplify","targeting":"channel=='nightly'"}
browser.ml.chat.prompts.3 {"id":"explain","l10nId":"genai-prompts-explain","targeting":"channel=='nightly'"} {"id":"quiz","l10nId":"genai-prompts-quiz","targeting":"!provider|regExpMatch('gemini') || region == 'US'"}
browser.ml.chat.shortcuts.custom false true
browser.ml.checkForMemory undefined false
browser.ml.defaultModelMemoryUsage undefined 2
browser.ml.maximumMemoryPressure undefined 80
browser.ml.minimumPhysicalMemory undefined 4
browser.ml.queueWaitInterval undefined 1
browser.ml.queueWaitTimeout undefined 60
browser.newtabpage.activity-stream.discoverystream.contextualContent.fakespot.ctaCopy undefined
browser.newtabpage.activity-stream.discoverystream.contextualContent.fakespot.ctaUrl undefined
browser.newtabpage.activity-stream.discoverystream.contextualContent.fakespot.defaultCategoryTitle undefined
browser.newtabpage.activity-stream.discoverystream.contextualContent.fakespot.enabled undefined true
browser.newtabpage.activity-stream.discoverystream.contextualContent.fakespot.footerCopy undefined
browser.newtabpage.activity-stream.discoverystream.contextualContent.feeds need_to_know need_to_know, fakespot
browser.newtabpage.activity-stream.discoverystream.spocs.startupCache.enabled true false
browser.newtabpage.activity-stream.newtabAdSize.variant-a undefined false
browser.newtabpage.activity-stream.newtabAdSize.variant-b undefined false
browser.newtabpage.activity-stream.support.url https://support.mozilla.org/1/firefox/132.0.2/Linux/en-US/new-tab https://support.mozilla.org/1/firefox/133.0/Linux/en-US/new-tab
browser.profiles.profile-name.updated undefined false
browser.tabs.groups.dragOverThresholdPercent undefined 20
browser.theme.native-theme undefined true
browser.urlbar.deduplication.enabled undefined false
browser.urlbar.deduplication.thresholdDays undefined 7
browser.urlbar.focusContentDocumentOnEsc undefined false
browser.urlbar.nerThreshold undefined 0.5
browser.urlbar.quicksuggest.mlEnabled undefined false
browser.urlbar.quicksuggest.rankingMode undefined default
browser.urlbar.suggest.quickactions undefined true
browser.urlbar.yelp.mlEnabled undefined false
devtools.debugger.features.codemirror-next false true
devtools.debugger.show-content-scripts undefined false
devtools.inspector.rule-view.starting-style true undefined
dom.cache.databaseInitialization.pauseOnIOThreadMs undefined 0
dom.element.dialog.toggle_events.enabled undefined true
dom.element.popover.enabled true undefined
dom.fetchKeepalive.enabled false true
dom.fetchKeepalive.request_limit_per_origin 30 250
dom.fetchKeepalive.total_request_limit 100 500
dom.fs.databaseInitialization.pauseOnIOThreadMs undefined 0
dom.fs.testing undefined false
dom.indexedDB.databaseInitialization.pauseOnIOThreadMs undefined 0
dom.media.webcodecs.image-decoder.enabled false true
dom.popup_maximum 20 -1
dom.quotaManager.artificialFailure.categories undefined 0
dom.quotaManager.artificialFailure.errorCode undefined 0
dom.quotaManager.artificialFailure.probability undefined 0
dom.quotaManager.originInitialization.pauseOnIOThreadMs undefined 0
dom.quotaManager.temporaryStorage.lazyOriginInitialization undefined false
dom.quotaManager.temporaryStorage.triggerOriginInitializationInBackground undefined false
dom.security.https_first_exception_lifetime undefined 604800000
dom.security.https_first_for_custom_ports undefined true
dom.server-events.default-reconnection-time 5000 undefined
dom.serverEvents.defaultReconnectionTime undefined 5000
dom.simpledb.databaseInitialization.pauseOnIOThreadMs undefined 0
dom.storage.databaseInitialization.pauseOnIOThreadMs undefined 0
dom.storage.enable_migration_from_unsupported_legacy_implementation undefined false
dom.storage.requestFinalization.pauseOnDOMFileThreadMs undefined 0
editor.block_inline_check.use_computed_style true undefined
extensions.script_about_blank_without_permission false undefined
extensions.webcompat-reporter.enabled false true
gfx.direct2d.disabled false true
javascript.options.dom_alloc_site undefined true
javascript.options.experimental.iterator_helpers true undefined
javascript.options.experimental.uint8array_base64 undefined true
javascript.options.wasm_call_ref_inlining undefined true
javascript.options.wasm_call_ref_inlining_percent undefined 50
javascript.options.wasm_direct_inlining undefined true
javascript.options.wasm_experimental_callRef_inlining true undefined
javascript.options.wasm_experimental_compile_pipeline false undefined
javascript.options.wasm_experimental_direct_inlining true undefined
javascript.options.wasm_experimental_inline_call_ref_threshold 1 undefined
javascript.options.wasm_experimental_inlining_level 5 undefined
javascript.options.wasm_experimental_tiering_level 5 undefined
javascript.options.wasm_inlining_level undefined 5
javascript.options.wasm_lazy_tiering undefined false
javascript.options.wasm_lazy_tiering_for_gc undefined false
javascript.options.wasm_lazy_tiering_level undefined 5
javascript.options.wasm_lazy_tiering_synchronous undefined false
layers.gpu-process.extend_ipc_reply_timeout_ms undefined 20000
layout.css.accent-color.min-contrast-ratio 3.0 2.4
layout.css.has-slotted-selector.enabled undefined false
layout.css.prefixes.transforms false true
media.gmp-manager.chromium-update-url undefined https://update.googleapis.com/service/update2/crx?response=redirect&x=id%3D%GUID%%26uc&acceptformat=crx3&updaterversion=999
media.gmp-widevinecdm.chromium-guid undefined oimompecagnajdejgnnjijobebaeigek
media.gmp-widevinecdm.force-chromium-beta undefined false
media.gmp-widevinecdm.force-chromium-update undefined false
media.wakelock.audio.delay-releasing.ms undefined 10000
network.cookie.useServerTime false true
network.dns.https_rr.check_record_with_cname undefined false
network.dns.port_prefixed_qname_https_rr false true
network.dns.skip_ipv6_when_no_addresses undefined false
network.http.http2.send_NO_RFC7540_PRI true false
network.http.http3.disable_when_third_party_roots_found false true
network.url.simple_uri_schemes undefined
network.url.simple_uri_unknown_schemes undefined
network.url.simple_uri_unknown_schemes_enabled undefined true
network.url.some_schemes_bypass_defaultURI_fallback true undefined
network.url.useDefaultURI false true
places.forgetThisSite.clearByBaseDomain true undefined
privacy.window.maxInnerHeight 1000 900
privacy.window.maxInnerWidth 1000 1400
reader.debug undefined false
remote.events.async.enabled undefined false
security.certerrors.felt-privacy-v1 undefined false
security.certerrors.recordEventTelemetry true undefined
security.pki.cert_trust_cache_size undefined 128
security.pki.crlite_channel specified all
security.pki.crlite_timestamps_for_coverage undefined 1
security.protectionspopup.recordEventTelemetry true undefined
sidebar.backupState undefined {}
signon.management.page.fileImport.enabled true undefined
toolkit.telemetry.enabled false true