fix(test): unflake screencast backpressure test on slow macOS runner#41951
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'applies backpressure while async onFrame callback is pending' timed out on the second `expect.poll` (frame delivery resuming after `releaseCallback`) at its default 10s budget. It reproduces only on the slower `chromium-macos-15-large` runner; the same test passes on macos-15-xlarge, macos-14-xlarge, and every Linux/Windows bot, so this is a time-budget problem under load, not a logic bug. The test already has `test.slow()` (90s), but the inner polls were capped at 10s. Give the two load-sensitive polls a 30s timeout. DB evidence (chromium-macos-15-large, rolling window): 24/31 runs failed (77.4%), all `Timeout 10000ms exceeded while waiting on the predicate` at screencast.spec.ts:99. Test was added 2026-07-21 in #41898; failures start the same day and continue through today. Fails on no other bot (macos-15-xlarge 0/31, macos-14-xlarge 0/31, all Linux 0/70). Run history (chromium-macos-15-large, oldest first): [🟥](https://github.com/microsoft/playwright/actions/runs/29835236639/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29838699822/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29844141129/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29845175984/attempts/1)[🟧](https://github.com/microsoft/playwright/actions/runs/29845392058/attempts/1)[🟧](https://github.com/microsoft/playwright/actions/runs/29855614229/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29855625844/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29856729151/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29859883032/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29865460136/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29866867131/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29867308985/attempts/1)[🟧](https://github.com/microsoft/playwright/actions/runs/29873996100/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29874748609/attempts/1)[🟩](https://github.com/microsoft/playwright/actions/runs/29874783963/attempts/1)[🟧](https://github.com/microsoft/playwright/actions/runs/29877078341/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29879172510/attempts/1)[🟩](https://github.com/microsoft/playwright/actions/runs/29904950059/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29915407358/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29918102409/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29924682554/attempts/1)[🟧](https://github.com/microsoft/playwright/actions/runs/29931173316/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29932910968/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29933325202/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29938598979/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29940740538/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29945241493/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29957712363/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29960743816/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/29986800439/attempts/1)[🟥](https://github.com/microsoft/playwright/actions/runs/30000526442/attempts/1) Verified on macos-15-large (this OS): before, `ctest screencast.spec.ts:57 --repeat-each=8` failed 2/8 at line 99; after, `--repeat-each=15` passed 15/15. `npm run flint` clean. CI run: https://github.com/microsoft/playwright/actions/runs/30001349050 Suggested-reviewer: Skn0tt
Contributor
Test results for "tests 1"3 flaky50206 passed, 1190 skipped Merge workflow run. |
Contributor
Test results for "MCP"1 failed 7785 passed, 1262 skipped Merge workflow run. |
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'applies backpressure while async onFrame callback is pending' timed out on
the second
expect.poll(frame delivery resuming afterreleaseCallback) atits default 10s budget. It reproduces only on the slower
chromium-macos-15-largerunner; the same test passes on macos-15-xlarge, macos-14-xlarge, and every
Linux/Windows bot, so this is a time-budget problem under load, not a logic bug.
The test already has
test.slow()(90s), but the inner polls were capped at 10s.Give the two load-sensitive polls a 30s timeout.
DB evidence (chromium-macos-15-large, rolling window): 24/31 runs failed (77.4%),
all
Timeout 10000ms exceeded while waiting on the predicateat screencast.spec.ts:99.Test was added 2026-07-21 in #41898; failures start the same day and continue through
today. Fails on no other bot (macos-15-xlarge 0/31, macos-14-xlarge 0/31, all Linux 0/70).
Run history (chromium-macos-15-large, oldest first):
🟥🟥🟥🟥🟧🟧🟥🟥🟥🟥🟥🟥🟧🟥🟩🟧🟥🟩🟥🟥🟥🟧🟥🟥🟥🟥🟥🟥🟥🟥🟥
Verified on macos-15-large (this OS): before,
ctest screencast.spec.ts:57 --repeat-each=8failed 2/8 at line 99; after,
--repeat-each=15passed 15/15.npm run flintclean.CI run: https://github.com/microsoft/playwright/actions/runs/30001349050
Suggested-reviewer: Skn0tt