feat(firefox): roll to r1543

[microsoft-playwright-automation]

Browser build: https://github.com/microsoft/playwright-browsers/commit/13cb1f3d8f4f145af38bec44c28b893f8a9110c0. Build has full platform coverage - check that all tests pass there.

[github-actions]

Test results for "MCP"

8275 passed, 1371 skipped

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Merge workflow run.

[github-actions]

Test results for "tests 1"

6 flaky

⚠️ [chromium-library] › library/video.spec.ts:664 › screencast › should capture full viewport `@realtime-time-library-chromium-linux`
⚠️ [chromium-library] › library/video.spec.ts:736 › screencast › should work with video+trace `@realtime-time-library-chromium-linux`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:257 › third party 'Partitioned;' cookies `@firefox-ubuntu-22.04-node20`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:470 › top level 'Partitioned;' cookie and same origin iframe `@firefox-ubuntu-22.04-node20`
⚠️ [firefox-library] › library/defaultbrowsercontext-2.spec.ts:139 › should create userDataDir if it does not exist `@firefox-ubuntu-22.04-node20`
⚠️ [firefox-page] › page/page-event-request.spec.ts:181 › should return response body when Cross-Origin-Opener-Policy is set `@firefox-ubuntu-22.04-node20`

51326 passed, 1247 skipped

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Merge workflow run.

[github-actions]

Test results for "tests 2"

4 failed
❌ [chromium-page] › page/page-route.spec.ts:277 › should work with custom referer headers @msedge-dev-windows-latest
❌ [chromium-page] › page/page-set-extra-http-headers.spec.ts:65 › should not duplicate referer header @msedge-dev-windows-latest
❌ [webkit-library] › library/browsercontext-storage-state.spec.ts:281 › should round-trip OPFS in a persistent WebKit context @webkit-windows-latest
❌ [webkit-page] › page/page-leaks.spec.ts:136 › expect should not leak @webkit-macos-15-xlarge

23 flaky

⚠️ [playwright-test] › ui-mode-test-watch.spec.ts:185 › should watch new file `@realtime-time-runner-chromium-linux`
⚠️ [chromium-page] › page/page-screenshot.spec.ts:504 › page screenshot › should take fullPage screenshots during navigation `@tracing-chromium`
⚠️ [chromium-library] › library/video.spec.ts:736 › screencast › should work with video+trace `@chromium-macos-14-xlarge`
⚠️ [chromium-library] › library/chromium/oopif.spec.ts:179 › should take screenshot `@chromium-macos-15-xlarge`
⚠️ [chromium-library] › library/chromium/chromium.spec.ts:301 › should report intercepted service worker requests in HAR `@chrome-macos-latest`
⚠️ [chromium-library] › library/chromium/chromium.spec.ts:373 › should produce network events, routing, and annotations for Service Worker `@chrome-macos-latest`
⚠️ [chromium-library] › library/selector-generator.spec.ts:93 › selector generator › should use description when name is not unique `@chrome-macos-latest`
⚠️ [chromium-library] › library/selector-generator.spec.ts:272 › selector generator › should use readable id `@chrome-macos-latest`
⚠️ [chromium-library] › library/selector-generator.spec.ts:323 › selector generator › should use parent text `@chrome-macos-latest`
⚠️ [chromium-library] › library/selector-generator.spec.ts:437 › selector generator › should prioritize attributes correctly › type `@chrome-macos-latest`
⚠️ [chromium-library] › library/video.spec.ts:152 › screencast › should continue recording main page after popup closes `@chrome-macos-latest`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:257 › third party 'Partitioned;' cookies `@tracing-firefox`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:470 › top level 'Partitioned;' cookie and same origin iframe `@tracing-firefox`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:257 › third party 'Partitioned;' cookies `@firefox-macos-15-large`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:470 › top level 'Partitioned;' cookie and same origin iframe `@firefox-macos-15-large`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:257 › third party 'Partitioned;' cookies `@firefox-windows-latest`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:470 › top level 'Partitioned;' cookie and same origin iframe `@firefox-windows-latest`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:257 › third party 'Partitioned;' cookies `@firefox-macos-15-xlarge`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:470 › top level 'Partitioned;' cookie and same origin iframe `@firefox-macos-15-xlarge`
⚠️ [webkit-library] › library/trace-viewer-scrub.spec.ts:157 › should update scrubber aria-valuenow `@webkit-macos-15-xlarge`
⚠️ [webkit-library] › library/tracing.spec.ts:533 › should produce screencast frames fit `@webkit-macos-15-xlarge`
⚠️ [webkit-library] › library/browsertype-connect.spec.ts:813 › launchServer › should upload a folder `@webkit-macos-15-large`
⚠️ [android-page] › page/page-autowaiting-no-hang.spec.ts:53 › calling window.open and window.close

110616 passed, 4739 skipped

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Merge workflow run.

[github-actions]

🟢 CI is clear — none of the failures are caused by this PR

Hi, I'm the Playwright bot and I took a look at the failing CI. This is a Firefox-only roll (browsers.json r1542→r1543 plus a Firefox juggler NetworkObserver.js tweak), and every failure in the latest report is on Chromium (msedge-dev) or WebKit — engines this PR doesn't touch. All four check out as pre-existing flakes or bot-specific breakage.

Details

The four failures in the latest "tests 2" report are all confirmed pre-existing in the aggregated CI results DB. Nothing here reaches Firefox code, so the roll can't be the cause.

Pre-existing flake / infra

• [chromium-page] › page/page-route.spec.ts:277 › should work with custom referer headers @msedge-dev-windows-latest — long-standing flake on this bot: failed 26 of 360 runs, and it fails across many unrelated SHAs including plain main pushes (e.g. 855c7349, 8f206e1c) and other PRs (chore(deps-dev): bump fast-uri from 3.1.3 to 3.1.7 #42516, chore(deps): bump actions/setup-java from 5.7.0 to 6.0.0 in the github-actions group across 1 directory #42523, feat(webkit): roll to r2359 #42493).
• [chromium-page] › page/page-set-extra-http-headers.spec.ts:65 › should not duplicate referer header @msedge-dev-windows-latest — a referer-header test failing on the same msedge-dev-windows-latest bot as the one above. Both are Chromium tests about Referer behavior tripping on the auto-updating Edge dev channel — an environment issue, not a Firefox roll.
• [webkit-library] › library/browsercontext-storage-state.spec.ts:281 › should round-trip OPFS in a persistent WebKit context @webkit-windows-latest — broken specifically on webkit-windows-latest: failed 14 of 14 runs there, while passing 42 times on other bots. Consistently red on that platform regardless of the PR.
• [webkit-page] › page/page-leaks.spec.ts:136 › expect should not leak @webkit-macos-15-xlarge — bimodal flake: failed 11 of 305 runs on this bot, passed the other 294.

Caused by this PR

• None.

For the record, the Firefox flakes that did show up (browsercontext-cookies-third-party Partitioned cookies, defaultbrowsercontext-2, page-event-request COOP) all passed on retry, so there's nothing to triage there either.

_{Triaged by the Playwright bot - agent run}