test: roll stable-test-runner to 1.64.0-alpha-2026-09-07

[microsoft-playwright-automation]

No description provided.

[github-actions]

Test results for "tests 1"

5 flaky

⚠️ [chromium-library] › library/popup.spec.ts:260 › should not throw when click closes popup `@chromium-ubuntu-22.04-arm-node20`
⚠️ [chromium-library] › library/video.spec.ts:664 › screencast › should capture full viewport `@chromium-ubuntu-22.04-arm-node20`
⚠️ [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-page] › page/page-event-request.spec.ts:181 › should return response body when Cross-Origin-Opener-Policy is set `@firefox-ubuntu-22.04-node20`

51359 passed, 1247 skipped

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Merge workflow run.

[github-actions]

Test results for "MCP"

1 failed
❌ [firefox] › mcp/annotate.spec.ts:386 › should cancel browser_annotate when the MCP request is aborted @mcp-windows-latest-firefox

8326 passed, 1371 skipped

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Merge workflow run.

[github-actions]

🟢 CI is clear — the one failure is a known flake

Hi, I'm the Playwright bot and I triaged the CI failures on this stable-test-runner roll.

The only failure — mcp/annotate.spec.ts:386 › should cancel browser_annotate when the MCP request is aborted on mcp-windows-latest-firefox — is a long-standing flake unrelated to this PR. This PR only bumps the @playwright/test version pinned in tests/playwright-test/stable-test-runner/, which the MCP suite doesn't exercise. Nothing here needs a fix.

Details

Overall: the diff is a two-file version bump (package.json + package-lock.json) rolling the stable-test-runner to 1.64.0-alpha-2026-09-07. That fixture only feeds a handful of playwright-test tests; it can't reach Firefox MCP tooling. The "tests 1" report had 0 failures (5 flaky, 51359 passed), so there's nothing to triage there.

Pre-existing flake / infra

• [firefox] › mcp/annotate.spec.ts:386 › should cancel browser_annotate when the MCP request is aborted (@mcp-windows-latest-firefox) — confirmed flake. Across the test-results DB this test failed 14 of 694 runs (~2%) on this exact bot while passing the other 680, and it flips verdict on SHAs and PRs that have nothing to do with this roll (e.g. fix(video): embed recording start time in WebM metadata #42478, feat(firefox): roll Firefox to M155 #42445, chore(chromium): switch linux arm64 to cft builds #42440, feat(test): add annotations to TestStepInfo #42388, feat(chromium): roll to r1242 #42356, fix(cli): parse negative numbers as arguments #42333, plus several push runs). It's Windows-Firefox-only — mcp-ubuntu-latest-firefox and mcp-macos-latest-firefox are 0/696 and 0/702 — which points at an abort-timing race in the test, not this change. Recent final verdicts on mcp-windows-latest-firefox (oldest → newest, last square is this PR's run):

  🟩🟩🟩🟧🟩🟩🟩🟩🟩🟩🟩🟩🟩🟩🟩🟥

_{Triaged by the Playwright bot - agent run}