Thanks to our new contributors 👽🐷🐰🐯🐻!

• Hamir Mahal @hamirmahal
• angad-sethi @angad-sethi
• Junaid Ramzan @ajuni880

Notable Changes

• remove first-meaningful-paint metric (#16047)

Core

• move simulator creation and network analysis to lib/lantern (#16003)
• handle target crash at any point (#15985)
• aria-allowed-role: fix title and description (#16042)
• inspector-issues: add shared dictionary issue (#15993)
• lantern: refactor to DevTools modules convention (#16071)
• lantern: rename files to PascalCase (#16068)
• lantern: remove last usages of Lighthouse NetworkRequest (#16067)
• lantern: remove usage of Lighthouse constants module (#16062)
• lantern: remove all LH types (#16061)
• lantern: move tbt-util.js to lib/lantern (#16058)
• lantern: separate TraceEngine specific code (#16051)
• lantern: extract main thread events w/o TraceProcessor (#16049)
• lantern: remove usage of Lighthouse's ProcessedNavigation (#16048)
• lantern: use LCP instead of FMP for TTI simulation bounds (#16046)
• lantern: use computed artifact to create graph using trace (#16040)
• lantern: rename NetworkRequest record to rawRequest (#16037)
• lantern: resolve some differences when using trace (#16033)
• lantern: create network graph from trace (experimental) (#16026)
• network: align headers end time with send when no data received (#16044)
• network: fix time units in network quiet calc (#16013)
• test: add generatable squoosh trace (#15997)
• test: add generatable trace for paint metrics (#15994)
• test: add generatable iframe trace (#15995)
• types: add missing fields to Result.Category and NodeDetails (#16006)

CLI

• stop treating chrome launcher kill() as async (#15998)

Deps

• upgrade puppeteer to 22.11.1 (#16070)
• upgrade chrome-launcher to 1.1.2 (#16069)
• upgrade puppeteer to 22.10.0 (#16054)
• upgrade third-party-web to 0.24.3 (#16055)
• upgrade axe-core to 4.9.1 (#16056)

I18n

• import (#16080)

Docs

• remove await from chrome.kill() (#15982)

Tests

• use newer traces in network-analyzer-test.js (#16043)
• default to 0 for network trace data length (#16041)
• update remaining old traces for Lantern (#16039)
• use new trace in metrics-test for pwa (#16025)
• update many test traces, support .json.gz (#16007)
• add timeout to runSmokeTest (#16017)
• fix devtools e2e test runner (#16018)
• reduce expected value of render-blocking-requests smoke (#16011)
• update interactive test trace (#16001)
• use new button class name for devtools run script (#15999)
• ci: remove reference to deleted smoke test (#16010)
• lantern: fix some tests not running (#16073)
• lantern: refactor to DevTools test convention (#16072)
• lantern: remove usage of devtoolsLog in simulator tests (#16065)
• lantern: remove usage of computed SpeedIndex (#16064)
• lantern: remove usage of computed PageDependencyGraph (#16063)
• lantern: use TraceEngine directly in test fixtures (#16057)
• lantern: remove Speedline from Lantern unit test for now (#16060)
• lantern: remove devtools log from tests (#16050)

Misc

• change connectionId from string to number (#15983)
• ci: fix deprecated node usage in checkout@v3 (#16022)
• strings: fix WebAuthetication typo (#16028)

Full Changelog

We expect this release to ship in the DevTools of Chrome 126, and to PageSpeed Insights within 2 weeks.

New Contributors

Thanks to our new contributors 👽🐷🐰🐯🐻!

• Ashley Rich @A5hleyRich
• MrAdib @JohnAdib

Notable Changes

PWA Category Removal

As per Chrome’s updated Installability Criteria, Lighthouse has removed the PWA category. For future PWA testing, users will be directed to use the updated PWA documentation.

SEO Category Reorganization

The SEO category has been updated to reflect the priorities of Google search in 2024. As such, several audits have been removed or moved to other categories:

• The is-crawlable audit is now weighted high enough to fail the SEO category on its own. (#15933)
• The viewport and font-size audits are no longer priorities for SEO, but are still important for UX in general so they have been moved to the best practices category. (#15930)
• The plugins audit is no longer a priority for SEO and has been removed. (#15928)
• The tap-targets audit is no longer a priority for SEO and has been replaced with the target-size audit in accessibility. (#15906)

Overall Savings Deprecation

The overallSavingsMs value on performance diagnostic audits has been deprecated (#15902). We recommend using metricSavings.LCP or metricSavings.FCP to understand the estimated metric savings of performance diagnostics.

🆕 New Audits

• The aria-conditional-attr, aria-deprecated-role and aria-prohibited-attr Axe checks have been added to the Lighthouse accessibility category. (#15963)
• The redirects-http audit has been brought back, but will only passively check for a http -> https redirect if the provided URL happens to be on http (#13548)

Other Audit Changes

• The layout-shifts-elements audit is removed. Improved layout shift information can be found in the layout-shifts audit. (#15931)
• The no-unload-listeners audit is removed. Unload listeners are deprecated and are still flagged in the deprecations and bf-cache audits. (#15874)
• The duplicate-id-active audit is removed because it's corresponding Axe check is deprecated. (#15900)
• The uses-rel-preload and preload-fonts audits have been moved to the experimental config. Preload advice is still on hold and these audits were already in a disabled state. (#15876)

💥 Breaking Changes

• split up CSSUsage artifact (#15952)
• remove budgets (#15950)
• remove relevant audits lists from config (#15878)
• remove ScriptElements artifact (#15879)
• config: use explicit diagnostic group (#15901)
• service-worker: remove service-worker gatherer (#15942)

Core

• remove pre-v10 compat for page graph construction (#15948)
• a11y: re-enable target-size hidden audit (#15888)
• driver: add sendCommandAndIgnore (#15913)
• gather: handle crash if CDP target crashes (#11840)
• lantern: always use flexible network ordering (#14612)
• lantern: remove LR statistics (#15946)
• lantern: inline rtt constant (#15944)
• lantern: add LanternError and adapter to LH error (#15937)
• lantern: correct overlapping tasks in CPU nodes (#15938)
• lantern: duplicate isNonNetworkProtocol in lib/lantern (#15936)
• lantern: replace usage of LH.Artifacts.ProcessedTrace (#15905)
• lantern: move lantern metrics to lib/lantern (#15875)
• metric: remove gatherContext mode check (#15899)
• render-blocking: use trace engine as the source of truth (#15839)
• runner: use early return for readability (#15914)
• seo: support Persian in link-text audit (#15949)
• target-size: use binary display mode (#15910)

Report

• fix hidden audit handling for non-perf categories (#15968)

Deps

• upgrade tldts-icann to 6.1.16 (#15967)
• upgrade third-party-web to 0.24.2 (#15966)
• upgrade puppeteer to 22.6.5 (#15951)

Clients

• viewer: stop using legacy DOM api (#15964)

I18n

• import (#15958)

Docs

• bug-report: require users to read FAQs (#14383)
• readme: add DeploymentHawk to the list of integrations (#15847)

Tests

• refresh sample artifacts (#15962)
• invalidate devtools build cache (#15947)
• update network target type expectations (#15916)

Misc

• deduplicate all the dom helpers (#15960)
• merge changelog from branch-11 (#15957)
• remove BenchmarkIndexes base artifact (#15941)
• update public gatherer list (#15940)
• remove residual lighthouse-cli file (#15935)
• use "processing duration" instead of "processing time" for INP (#15893)
• treemap: fix column sorting when some values are blank (#15959)

Full Changelog

We expect this release to ship in the DevTools of Chrome 125, and to PageSpeed Insights within 2 weeks.

New Contributors

Thanks to our new contributors 👽🐷🐰🐯🐻!

• lauren n. liberda @selfisekai

Core

• network-request: recognize zstd compression algorithm (#15883)
• trace-elements: add sentry debugging for impactedNodes (#15915)
• trace-processor: correct overlapping tasks (#15921)

Report

• remove use of innerHTML to empty elements (#15911)

Deps

• upgrade trace_engine to 0.0.19 (#15926)
• upgrade axe-core to 4.9.0 (#15887)

Tests

• remove Access-Control-Allow-Origin for robots.txt (#15895)
• devtools: sync e2e (#15917)

Misc

• correct .npmignore for node >=18.20 (#15924)
• proto: ensure all strings are well-formed (#15909)

Full Changelog

We expect this release to ship in the DevTools of Chrome 125, and to PageSpeed Insights within 2 weeks.

Notable Changes

• The publisher ads plugin is out of date and will not be supported in Chrome DevTools M125 (#15843)

Core

• fix regression in internal chrome error messages (#15853)
• a11y: disable target-size hidden audit (#15854)
• css-usage: prevent late stylesheet additions (#15865)
• driver: don't await cleanup in PAGE_HUNG case (#15833)
• driver: fix protocol timeout being ignored for isolated eval (#15826)
• emulation: remove Lighthouse from client hint brand (#15856)
• full-page-screenshot: emit screenshot commands in parallel (#15862)
• full-page-screenshot: revise logic for determining dimensions (#14920)
• gather: gatherFn refactor (#15830)
• installable-manifest: add manifest-parsing-or-network-error (#15849)
• lantern: move types to lib/lantern (#15859)
• lantern: move LanternMetric in lib/lantern (#15857)
• lantern: refactor LH.Gatherer.Simulation (#15852)
• lantern: move PageDependencyGraph to lib/lantern (#15851)
• lantern: put types in namespace (#15850)
• lantern: rename lib/dependency-graph to lib/lantern (#15844)
• lantern: add interface for network request (#15845)
• lantern: use rendererStartTime instead of networkRequestTime (#15834)
• navigation-runner: only run getArtifact phase once (#15827)
• network-request: use rendererStartTime for initiator candidates (#15832)
• responsiveness: remove fallback trace event pre m103 (#15866)

Deps

• upgrade chrome-launcher to 1.1.1 (#15871)
• upgrade puppeteer to 22.5.0 (#15867)
• bump ip from 1.1.8 to 1.1.9 (#15863)

I18n

• import (#15872)

Tests

• devtools: use is_debug = true for local builds (#15860)
• devtools: skip type checking in local builds (#15858)
• devtools: sync e2e (#15837)
• full-page-screenshot: add node verification and debug tool (#15324)

Full Changelog

We expect this release to ship in the DevTools of Chrome 124, and to PageSpeed Insights within 2 weeks.

Notable Changes

• trace: disable JS samples (#15819)

Core

• driver: add verbose logs for wait-for page load components (#15818)

Deps

• upgrade puppeteer to 22.1.0 (#15822)
• upgrade trace_engine and drop manually written types (#15810)
• upgrade axe-core to 4.8.4 (#15805)
• upgrade puppeteer to 22.0.0 (#15803)

I18n

• import (#15821)

Tests

• dbw: revert expectations for unload handler removal (#15802)

Misc

• reword pwa banner (#15800)
• do not double report artifact dep error to sentry (#15777)

Full Changelog

We expect this release to ship in the DevTools of Chrome 123, and to PageSpeed Insights within 2 weeks.

New Contributors

Thanks to our new contributors 👽🐷🐰🐯🐻!

• EvilKarter @EvilKarter

Notable Changes

• New layout-shifts audit shows estimated root causes for layout shifts. This replaces the layout-shift-elements audit which only shows elements impacted by layout shifts. (#15703, #15730)
• Informative audits now have a score of 1 instead of null (#15689)
• Added a warning for PWA deprecation (#15741)

Core

• bump guidance level of top CWV recommendations (#15695)
• lower guidance level of unused- audits (#15718)
• create separate product savings type (#15726)
• round metric savings to remove false precision (#15721)
• fix mistake preventing gather/audit phases from sharing cache (#15710)
• cumulative-layout-shift: experiment with new shared trace engine (#15702)
• legacy-javascript: detect es-shims polyfills (#15738)
• network-request: consider secondary headers for content encoded check (#15708)
• render-blocking-resources: reduce metric savings if LCP is an image (#15694)
• target-manager: warn on errors while attaching to workers (#15740)
• trace: enable JS samples for advanced workflows (#15542)
• unused-css: exclude header size for estimating wasted bytes (#15671)
• viewport: include meta viewport string in debugDetails (#15727)

Report

• small renderAudit simplification (#15725)
• fix filmstrip wrap (#15693)
• performance: use metric savings for metric filter (#15540)

Deps

• upgrade puppeteer to 21.7.0 (#15724)
• upgrade esbuild to 0.19.11 (#15731)

Clients

• lr: include flag for ignoring bad page status code (#15764)

Docs

• update deprecated link to shared flags (#15722)
• user-flows: update complete flow example (#15690)

Tests

• check for console errors and warnings in pptr tests (#15516)
• fix ToT chrome install path (#15753)
• ci: stop using xvfb (#15707)
• dbw: update expectations for unload handler removal (#15765)
• dbw: fix server latency flake (#15729)
• mocha: fix snapshot expectations in retries (#15735)

Misc

• build: set line limit to 1000 (#15733)
• lighthouse-logger: add repo to package.json (#15768)

Full Changelog

We expect this release to ship in the DevTools of Chrome 122, and to PageSpeed Insights within 2 weeks.

New Contributors

Thanks to our new contributors 👽🐷🐰🐯🐻!

• avinash-sd @avinash-sd

New Audits

Chrome plans to remove support for third-party cookies which can be detected using a new Lighthouse audit. Learn more about phasing out third-party cookies. (#15632)

Core

• reintroduce resource-summary as a hidden audit (#15597)
• move transfer ratio estimate to script-helpers.js (#15665)
• set network responseHeadersText from extra info event (#15639)
• fix check for presence of all URL artifact fields (#15648)
• fix worker request expectations for M121 (#15601)
• aria-allowed-role: fix typo in learn more link (#15633)
• bf-cache: add warning and hide when using old headless (#15577)
• bf-cache: change to use binary scoring mode (#15581)
• bootup-time: exclude _lighthouse-eval.js (#15678)
• byte-efficiency: replace pessimistic graph with optimistic (#15651)
• css-usage: exclude empty stylesheets (#15679)
• duplicated-javascript: exclude header size for estimating wasted bytes (#15667)
• emulation: bump chrome UA to m119 (#15661)
• entity-classification: update tldts package to icann subset (#15660)
• entity-classification: integrate public-suffix-list into LH (#15641)
• lantern: refactor fcp graph method signatures (#15572)
• layout-shift-elements: mention windowing in description (#15680)
• layout-shift-elements: aggregate all remaining elements (#15593)
• legacy-javascript: exclude header size for estimating wasted bytes (#15640)
• minification-estimator: add else to punctuation (#15624)
• mpfid: add list of loaf durations to debugdata (#15685)
• mpfid: add max LoAFs to debugdata (#15684)
• third-party-summary: expands the audit to include all urls (#15611)
• trace-elements: remove element score field (#15677)
• unminified-javascript: exclude header size for estimating wasted bytes (#15670)
• unused-javascript: exclude header size for estimating wasted bytes (#15668)
• uses-http2: include multiplexable assets when 1p is a known 3p origin (#15638)

Report

• blend impact and guidance level to sort audits (#15669)
• fix sticky table if no sticky header (#15666)
• occupy entire viewport (#15664)
• remove accidental console.log() (#15635)
• prevent shift when hovering third party row (#15628)
• add timespan/snapshot mode labels to footer (#15589)

Deps

• upgrade third-party-web to 0.24.1 (#15683)
• upgrade puppeteer to 21.5.2 (#15645)

Clients

• lr: modify puppeteer connector to work with new tab targets (#15674)

I18n

• import (#15682)

Tests

• lower bootup-time threshold in api-test-pptr.js (#15649)
• use bash instead of sh to call test-recipes.sh (#15647)
• ci: resume using ToT chrome (#15655)
• ci: hardcode ToT revision to unblock ci for now (#15653)
• dbw: add unload handler deprecation (#15608)

Misc

• improve download-chrome.sh usability (#15646)
• support mac arm64 in download-chrome.sh (#15650)
• treemap: remove unused firebase (#15617)

Full Changelog

We expect this release to ship in the DevTools of Chrome 121, and to PageSpeed Insights within 2 weeks.

New Contributors

Thanks to our new contributors 👽🐷🐰🐯🐻!

• Max Coplan @vegerot
• Barry Pollard @tunetheweb

Notable Changes

• core: add clearStorageTypes option (#15508)
• core: create flag to prevent fatal error on bad status code (#15494)
• clients(extension): add locale selector (#15574)
• clients(extension): always show settings, add psi frontend (#15526)

Core

• remove config navigations (#15397)
• accessibility: hide experimental axe rules (#15543)
• inspector-issues: add cookie deprecation issue (#15553)

Report

• use normal gauge if performance score is null (#15554)

Deps

• upgrade puppeteer to 21.5.0 (#15582)
• upgrade lighthouse-stack-packs to 1.12.1 (#15566)
• upgrade puppeteer to 21.4.0 (#15557)

Clients

• devtools: default to ignore fatal errors (#15558)

I18n

• import (#15579)

Docs

• plugins: add link to GitHub repo template (#15539)

Tests

• use --headless=new for all smoketests (#14419)
• devtools: extend protocol timeout for load (#15555)
• devtools: sync e2e (#15550)

Misc

• update web.dev URLs (#15534)

Full Changelog

We expect this release to ship in the DevTools of Chrome 120, and to PageSpeed Insights within 2 weeks.

Notable Changes

This update includes an overhaul to the performance category. Performance insights are now scored and prioritized based on their estimated impact to the performance metrics. Additionally, the performance score gauge includes more detailed information about how each metric affects the score.

• core: align performance audit score with metric savings (#15447)
• report: sort performance audits based on impact (#15445)
• report: add explodey gauge for performance category (#15396)

Core

• asset-saver: fix handling of undefined trace (#15451)
• csp: use monospace for technical terms in strings (#15511)
• driver: attach to worker targets (#14212)
• inspector-issues: add propertyRuleIssue (#15491)
• installable-manifest: use monospace for technical terms in strings (#15513)
• long-tasks: compute TBT impact (#15197)
• mainthread-work-breakdown: add TBT savings (#15201)
• tags-blocking-first-paint: ignore malformed link tags (#15489)

CLI

• sentry: set useful tags from resolved config (#15485)

Report

• redefine gauge percentage positioning (#15486)

Deps

• upgrade puppeteer to v21.3.6 (#15490)
• pin puppeteer version (#15458)
• upgrade axe-core to 4.8.1 (#15446)
• chrome-launcher: upgrade to 1.1.0 (#15517)

Clients

• viewer: fix preload links (#15515)

I18n

• upgrade to latest icu formatter (#13834)

Docs

• plugins: minor corrections (#15449)
• readme: edit description of the PageVitals tool (#15395)

Tests

• use new headless for puppeteer tests (#15374)
• dbw: increase wasted ms threshold (#15483)
• devtools: remove usage of frontend globals (#15518)
• devtools: ensure Lighthouse starts in smoke tests (#15459)
• devtools: fix viewport in smoke tests (#15454)
• devtools: sync e2e (#15444)

Misc

• tweak dependabot ecosystem value (#15521)
• have dependabot check github actions deps (#15496)
• adopt minimal license headers (#15456)
• bot: delete stale git bot rules (#14915)
• ci: use commit sha for markdown action (#15493)

Full Changelog

We expect this release to ship in the DevTools of Chrome 119, and to PageSpeed Insights within 2 weeks.

New Contributors

Thanks to our new contributors 👽🐷🐰🐯🐻!

• Tortitas @TortitasT
• Ian Kilpatrick @bfgeek
• GLI @tobyglei

Core

• add TBT savings to bootup-time (#15431)
• add guidance level to performance audits (#15025)
• add TBT impact to third party audits (#15385)
• fix index.cjs types (#15387)
• asset-saver: use new DevtoolsLog and Trace artifacts (#15345)
• crawlable-anchors: consider empty rawHref crawlable (#15406)
• dom-size: add TBT savings (#15307)
• image-aspect-ratio: loosen aspect ratio threshold (#15328)
• installable-manifest: update available installability errors (#15388)
• largest-contentful-paint-element: add LCP savings (#15178)
• lcp-lazy-loaded: add LCP savings estimate (#15064)
• main-resource: fix protocol error when page is reloaded (#14520)
• redirects: score only on wasted ms (#15401)
• timespan-runner: warn if a navigation is detected (#15407)
• viewport-meta: include initial-scale value condition (#15394)

Report

• fix category highlight in DevTools (#15413)

Deps

• upgrade third-party-web to 0.24.0 (#15354)
• upgrade axe-core to 4.8.0 (#15430)
• upgrade puppeteer to 21.1.1 (#15403)
• upgrade puppeteer to 20.0.3 (#15375)

Clients

• extension: update some properties for manifest v3 (#15347)

I18n

• import (#15443)

Docs

• update explainer for devtools build (#15414)
• add a guide to running Lighthouse at scale (#10511)
• readme: fix chrome-launcher import example (#15428)
• readme: add Lighthouse Metrics China to services list (#15256)
• releasing: update cadence section (#15392)
• releasing: remove instructions covered by automated tests (#15353)

Tests

• better error handling when test modules fail to load (#15421)
• do not allow hashes in mock dt log (#15363)
• dbw: remove upper bound for LCP load start/end (#15432)
• dbw: increase threshold for LCP load start/end (#15393)
• devtools: sync e2e (#15389)
• smoke: update installability icon error for ToT (#15422)
• unit: retry failures and upload failure artifacts (#15378)

Misc

• move root.js to shared/ (#15439)
• remove url hash to avoid gtm hang in treemap, viewer (#15425)
• move esm-utils.js to shared/ (#15418)
• move dependabot.yml to correct folder (#15417)
• add dependabot.yml (#15341)
• build: do not minify browser extension (#15381)
• build: output source map when building bundles (#15348)
• readme: use note for Node version callout (#15410)
• treemap: reduce granularity for byte values (#15415)