This is difference between the default preference of Firefox 102.0 beta 3 and one of 101.0. This diff table is generated with my small script firefox-prefjs-surveyer.

Preference difference
PrefFirefox 101.0Firefox 102.0 beta 3
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-browser&utm_campaign=whatsnew https://www.mozilla.org/%LOCALE%/firefox/%VERSION%beta/releasenotes/?utm_source=firefox-browser&utm_medium=firefox-browser&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.cache.jsbc_compression_level undefined 0
browser.cache.offline.enable true false
browser.contentblocking.features.strict tp,tpPrivate,cookieBehavior5,cookieBehaviorPBM5,cm,fp,stp,lvl2,rp,rpTop,ocsp tp,tpPrivate,cookieBehavior5,cookieBehaviorPBM5,cm,fp,stp,lvl2,rp,rpTop,ocsp,qps
browser.download.start_downloads_in_tmp_dir undefined false
browser.newtabpage.activity-stream.colorway-closet.enabled false undefined
browser.newtabpage.activity-stream.discoverystream.sendToPocket.enabled undefined false
browser.newtabpage.activity-stream.discoverystream.widget-positions undefined
browser.newtabpage.activity-stream.telemetry.ut.events false true
browser.proton.places-tooltip.enabled false undefined
browser.snapshots.relevancy.timeOfDayIntervalSeconds undefined 3600
browser.snapshots.source.TimeOfDay undefined 3
browser.tabs.firefox-view undefined false
browser.urlbar.autoFill.adaptiveHistory.enabled undefined false
browser.urlbar.autoFill.adaptiveHistory.minCharsThreshold undefined 0
devtools.netmonitor.features.newEditAndResend false true
devtools.performance.memory.max-log-length 125000 undefined
devtools.performance.memory.sample-probability 0.05 undefined
devtools.performance.new-panel-enabled true undefined
devtools.performance.profiler.buffer-size 10000000 undefined
devtools.performance.profiler.sample-frequency-hz 1000 undefined
devtools.performance.timeline.hidden-markers ["Composite","CompositeForwardTransaction"] undefined
devtools.performance.ui.enable-allocations false undefined
devtools.performance.ui.enable-framerate true undefined
devtools.performance.ui.enable-memory false undefined
devtools.performance.ui.enable-memory-flame false undefined
devtools.performance.ui.experimental false undefined
devtools.performance.ui.flatten-tree-recursion true undefined
devtools.performance.ui.invert-call-tree true undefined
devtools.performance.ui.invert-flame-graph false undefined
devtools.performance.ui.show-idle-blocks true undefined
devtools.performance.ui.show-jit-optimizations false undefined
devtools.performance.ui.show-platform-data false undefined
devtools.performance.ui.show-triggers-for-gc-types TOO_MUCH_MALLOC ALLOC_TRIGGER LAST_DITCH EAGER_ALLOC_TRIGGER undefined
dom.block_external_protocol_navigation_from_sandbox false true
dom.events.asyncClipboard.read false undefined
dom.image-lazy-loading.root-margin.bottom 300.0 100.0
dom.image-lazy-loading.root-margin.bottom.percentage false true
dom.image-lazy-loading.root-margin.left 300.0 100.0
dom.image-lazy-loading.root-margin.left.percentage false true
dom.image-lazy-loading.root-margin.right 300.0 100.0
dom.image-lazy-loading.root-margin.right.percentage false true
dom.image-lazy-loading.root-margin.top 300.0 100.0
dom.image-lazy-loading.root-margin.top.percentage false true
dom.importMaps.enabled undefined false
dom.mozCurrentTransform.enabled undefined false
dom.mozPaintCount.enabled false undefined
dom.origin-trials.enabled false true
dom.origin-trials.offscreen-canvas.state undefined 0
dom.storage.abort_on_sync_parent_to_child_messages false undefined
dom.storage.enable_unsupported_legacy_implementation undefined false
dom.storage.next_gen true undefined
dom.storage.shadow_writes true false
dom.streams.byte_streams.enabled false true
dom.streams.transferable.enabled undefined false
dom.streams.transform_streams.enabled false true
dom.webcomponents.disabledFeatures.enabled true undefined
dom.webcomponents.elementInternals.enabled true undefined
dom.webcomponents.formAssociatedCustomElement.enabled true undefined
dom.webidl.crosscontext_hasinstance.enabled true false
dom.webmidi.enabled false true
dom.window.sidebar.enabled true false
extensions.formautofill.addresses.ignoreAutocompleteOff undefined true
extensions.formautofill.creditCards.heuristics.mode 0 2
extensions.formautofill.creditCards.ignoreAutocompleteOff undefined true
extensions.pocket.refresh.layout.enabled false true
extensions.webcompat-reporter.enabled false true
extensions.webextensions.base-content-security-policy script-src 'self' https://* http://localhost:* http://127.0.0.1:* moz-extension: blob: filesystem: 'unsafe-eval' 'unsafe-inline'; object-src 'self' moz-extension: blob: filesystem:; script-src 'self' https://* http://localhost:* http://127.0.0.1:* moz-extension: blob: filesystem: 'unsafe-eval' 'wasm-unsafe-eval' 'unsafe-inline'; object-src 'self' moz-extension: blob: filesystem:;
extensions.webextensions.base-content-security-policy.v3 script-src 'self' http://localhost:* http://127.0.0.1:*; object-src 'self'; script-src 'self' 'wasm-unsafe-eval' http://localhost:* http://127.0.0.1:*; object-src 'self';
extensions.webextensions.default-content-security-policy script-src 'self'; object-src 'self'; script-src 'self' 'wasm-unsafe-eval'; object-src 'self';
extensions.webextensions.default-content-security-policy.v3 undefined script-src 'self'; object-src 'self';
geo.provider.geoclue.always_high_accuracy undefined true
geo.provider.network.url https://www.googleapis.com/geolocation/v1/geolocate?key=%GOOGLE_LOCATION_SERVICE_API_KEY% https://location.services.mozilla.com/v1/geolocate?key=%MOZILLA_API_KEY%
geo.provider.use_geoclue undefined true
gfx.canvas.accelerated.reserve-empty-cache undefined 36
gfx.display.frame-rate-divisor undefined 1
gfx.webrender.svg-images false true
html5.inert.enabled false true
javascript.options.streams true undefined
javascript.options.wasm_caching false true
javascript.options.wasm_simd_wormhole undefined false
javascript.options.writable_streams false undefined
layout.css.line-height.normal-as-resolved-value.enabled true undefined
layout.display_partial_background_images undefined true
layout.dynamic-reflow-roots.enabled false true
layout.throttle_in_process_iframes undefined true
media.cubeb.slow_stream_init_ms undefined 0
media.utility-process.enabled false true
media.webrtc.platformencoder.sw_mft false true
network.cache.frecency_array_check_enabled false true
network.cookie.sameSite.laxByDefault false true
network.cookie.sameSite.noneRequiresSecure false true
network.cookie.sameSite.schemeful false true
network.early-hints.enabled undefined false
network.jar.record_failure_reason false true
network.predictor.enable-prefetch false true
pdfjs.pageColorsBackground undefined Canvas
pdfjs.pageColorsForeground undefined CanvasText
print.show_print_progress true undefined
privacy.annotate_channels.strict_list.enabled false true
privacy.query_stripping.enabled.pbmode undefined false
security.ask_for_password 0 undefined
security.block_fileuri_script_with_wrong_mime undefined true
security.cancel_non_local_loads_triggered_by_systemprincipal false undefined
security.csp.wasm-unsafe-eval.enabled undefined true
security.directory undefined
security.disallow_non_local_systemprincipal_in_tests undefined false
security.disallow_privileged_https_script_loads undefined true
security.disallow_privileged_no_finaluri_loads undefined true
security.disallow_privilegedabout_remote_script_loads undefined true
security.intermediate_preloading_healer.enabled false true
security.nocertdb undefined false
security.password_lifetime 30 undefined
security.pki.sha1_enforcement_level 3 1
security.remote_settings.crlite_filters.bucket security-state undefined
security.remote_settings.crlite_filters.checked 0 undefined
security.remote_settings.crlite_filters.collection cert-revocations undefined
security.remote_settings.crlite_filters.enabled false true
security.remote_settings.crlite_filters.signer onecrl.content-signature.mozilla.org undefined
security.remote_settings.intermediates.bucket security-state undefined
security.remote_settings.intermediates.checked 0 undefined
security.remote_settings.intermediates.collection intermediates undefined
security.remote_settings.intermediates.signer onecrl.content-signature.mozilla.org undefined
security.ssl.disable_session_identifiers undefined false
security.tls13.aes_128_gcm_sha256 undefined true
security.tls13.aes_256_gcm_sha384 undefined true
security.tls13.chacha20_poly1305_sha256 undefined true
services.blocklist.addons-mlbf.checked 0 undefined
services.blocklist.addons.checked 0 undefined
services.blocklist.addons.collection addons undefined
services.blocklist.addons.signer remote-settings.content-signature.mozilla.org undefined
services.blocklist.bucket blocklists undefined
services.blocklist.gfx.checked 0 undefined
services.blocklist.gfx.collection gfx undefined
services.blocklist.gfx.signer remote-settings.content-signature.mozilla.org undefined
services.blocklist.plugins.checked 0 undefined
services.blocklist.plugins.collection plugins undefined
services.blocklist.plugins.signer remote-settings.content-signature.mozilla.org undefined
services.settings.default_bucket main undefined
services.settings.security.onecrl.bucket security-state undefined
services.settings.security.onecrl.checked 0 undefined
services.settings.security.onecrl.collection onecrl undefined
services.settings.security.onecrl.signer onecrl.content-signature.mozilla.org undefined
services.settings.server https://firefox.settings.services.mozilla.com/v1 undefined
services.sync.engine.bookmarks.validation.enabled undefined true
services.sync.engine.passwords.validation.enabled undefined true
services.sync.prefs.sync.privacy.resistFingerprinting true undefined
toolkit.telemetry.enabled false true
webgl.colorspaces.prototype undefined false
widget.swipe.success-threshold 0.25 undefined