5.2.0 (2019-07-24)

Expected DevTools release in Chrome 77 (September 2019)

New Audits

• Third-Party Usage, a new performance diagnostic that shows a breakdown of third-party resources in the page and the time/bytes needed to load them (#9067)
• Total Blocking Time, an experimental new metric that serves as a companion to TTI to help prioritize unblocking the main thread. Since it is currently experimental, the audit is unscored and appears only in the raw LHR JSON, not in the HTML report. (#8975, #9409)

Notable changes

• tracehouse: performance trace processing has been moved to its own directory in lib/tracehouse/ to serve as a more standalone library (9f80524, 1af2edd, 7ba6776, ddff3d6)
• certificate security errors are no longer a fatal Lighthouse error, though the Chrome error page will still return few results in the report by default. See the docs for testing a page in this situation. (#8865)

New contributors!

Thanks to @angelogulina, @jamesgeorge007, @johnemau, @kaushikchaubal, @mitchellsimoens, @NickolasBenakis, @noelyoo, @PatOnTheBack, @rishichawda, and @Remexllee for their first contributions!

Core

• support saving and loading errors in artifacts (#9397)
• config: assert all audit requiredArtifacts will be gathered (#9284)
• domstats: support an empty html body (#9340)
• font-display: limit false positives (#9148)
• font-size: calculate accurate line/column for styles (#9356)
• font-size: comment why source 'Other' occurs (#9363)
• localize invalid-URL error message (#9334)
• gather-runner: add PageLoadError base artifact (#9236)
• gather-runner: don't save trace on pass with pageLoadError (#9198)
• gather-runner: treat Chrome interstitials as pageLoadErrors (#9176)
• gather-runner: always reset scroll position (#9060)
• gather-runner: convert PAGE_HUNG to non-fatal runtimeError (#9121)
• manifest-parser: handle blob manifests (#9088)
• page-functions: don't try to clone a ShadowRoot (#9079)
• perf: speed up tap-target's isVisible() (#9056)
• tracehouse: allow missing FCP (#9174)

CLI

• accept flags from a file (#9109)

Clients

• devtools: audits2->audits and defer reading resources (#8985, #9344)
• devtools: unset overflow in print (#9274)
• lightrider: update processForProto method signature, string -> LH.Result (#9016)
• lightrider: serialize errors in artifacts (#9410)

Deps

• update axe-core to 3.3.0 (#9343)
• update typescript to 3.5.3 (#9357)
• update chrome-launcher to 0.11.1 (#9339)
• intl: move from devDep to dep (#9309)
• update debug to 2.6.9 (#9398)
• update to open from opn (#9267)
• update outdated transitive deps (#9347)
• update brfs to 2.0.2 (#9312)
• remove commitizen as local dep (#9246)
• update extend to 3.0.2 (#9184)
• bump transitive dep js-yaml (#9131)
• update bundlesize, add more budgets (#9089)

Docs

• add i18n overview and authoring documentation (#9361)
• link to good first issues (#9440)
• add instructions for testing with self-signed certificate (#9112)
• update understanding-results.md (#9226)
• change score type from 'string' to 'number' (#9225)
• readme: add Exthouse to related projects (#9243)
• readme: add lighthouse-jest-example to related projects (#9172)
• readme: add lighthouse-persist to related projects(#9161)
• readme: add gimbal integration to related projects (#9083)
• readme: update lighthouse-mocha-example related project (#9158)
• readme: alphabetize related projects (#9110)
• fix various typos (#9411)

I18n

• introduce script to swap in new locale to LHR (#8755)
• enable local debug locale, en-XL (#9192)
• begin localization of audits in best-practices (#9092)
• add es-419 (#9171)
• localize column headers of budget audits (#9127)

Report

• fix audit explanation rendering (#9439)
• accessibility: add heading role to report category gauge (#9422)
• add link to docs on performance scoring (#9355)
• use full-bleed image thumbnails (#9238)
• show disabled checkbox when all/no urls are third party (#9299)
• remove unnecessary attribute in svg (#9301)
• make urls clickable (#9224)
• use css grid for metrics (#9273)
• center and style top-level runtimeError (#9271)
• create naming convention for css variables (#9149, 37f7261, ece89ec)
• add aria-labels to tools button and metric toggle (#9201)
• update permalink calculations for correct hash nav scroll position (#9188)
• devtools: enable report UI features (#9157)
• position sticky-header highlighter with css grid (#9186)
• ensure SVG elements in <defs> have unique ids (#9151)
• only print light theme (#9173)
• make 'tools' menu focus-able (#9169)
• rename 'exports' to 'tools' (#9135)
• remove unused css vars (#9144)

Tests

• relax contrast font size expectation (#9441)
• font-size: assert on source (#9400, #9413)
• assert vulnerable-library ranges have upper bounds (#9308)
• i18n: update canonical locale test for node 12.6 (#9396)
• i18n: throw when no ICU replacement value is given (#9384)
• run CI with a frozen yarn.lock (#9362)
• smokehouse: assert on expected array length (#9292)
• smokehouse: always assert lhr.runtimeError (#9130)
• tags-blocking-first-paint: make alternate stylesheets not blocking (#9248)
• improve drag-and-drop test coverage (#9314)
• clean up crufty gather-runner tests (#9227)

Misc

• fix yarn.lock and translations master drift (#9404)
• build: adjust deployment filenames (#9338, #9434)
• build: create error-y LHR for the deploy (#9283)
• network-server-latency: fix serverResponseTime typo (#9388)
• localize logged GatherRunner error (#9291)
• remove duplicate colon from regex (#9295)
• runner: add assertion for devtoolsLog as requiredArtifact (#9290)
• add yarn static-server script (#9293)
• fix typo in performance-budget smoke test (#9244)
• add .idea to .gitignore for WebStorm developers (#9275)
• build: generate report variants in deployment (#9280)
• suggest uploading issue repro (#9217)
• use CHROME_PATH variable in CI and scripts (#9202)
• update broken tracing-processor require (#9123)
• address release script feedback (#9111)
• release script should commit with format vX.Y.Z (#9090)

Full 5.2.0 Changelog