test: enable setOffline test on chromium after roll

[Dmitry Gozman (dgozman)]

Closes #42174.

[github-actions]

Test results for "tests 1"

5 flaky

⚠️ [chromium-library] › library/beforeunload.spec.ts:130 › should support dismissing the dialog multiple times `@chromium-ubuntu-22.04-arm-node20`
⚠️ [chromium-library] › library/chromium/chromium.spec.ts:213 › should intercept service worker requests (main and within) `@chromium-ubuntu-22.04-node24`
⚠️ [chromium-library] › library/video.spec.ts:356 › screencast › should work for popups `@chromium-ubuntu-22.04-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`

52285 passed, 1249 skipped

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Merge workflow run.

[github-actions]

Test results for "MCP"

1 failed
❌ [firefox] › mcp/cli-drag.spec.ts:19 › drag between elements @mcp-windows-latest-firefox

8750 passed, 1480 skipped

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Merge workflow run.

[github-actions]

Hi, I'm the Playwright bot and I took a first look at the CI failures here.

🟢 The only failure is a known flake — unrelated to this PR

mcp/cli-drag.spec.ts:19 on Windows Firefox has failed on plenty of other runs, including pushes to main.

Details

The PR only touches tests/library/browsercontext-basic.spec.ts, where it re-enables the setOffline test on Chromium. That doesn't touch MCP, the CLI, or drag-and-drop, and there are no failures in the library suites.

Pre-existing flake / infra

• [firefox] › mcp/cli-drag.spec.ts:19 › drag between elements (mcp-windows-latest-firefox): a known flake. In the test-results DB it failed 14 of 707 runs (~2%) on this bot. That includes pushes to main (8db8731, 0a2a33c, b856094, 654654f) and unrelated PRs (fix(docs): document credentials, opfs, and indexeddb in storageState #42761, fix(debug-controller): drop recorded actions when recording session ends #42458, fix(reporter): fail perfetto writes when the output stream errors #42715, feat(mcp): add media emulation #42668, feat(trace-viewer): show screencast frames during playback #42751, test: fix click tests on android #42726, fix(highlight): highlight in the world the selector resolves in #42864, test(client-certificates): do not reuse a renegotiated connection #42878, fix(trace-viewer): label filter inputs and keyboard-accessible error source #42469). It's also Windows-only: 0 failures in 713 Ubuntu runs and 718 macOS runs. It failed on an earlier commit of this PR (fc3c11e) as well.

_{Triaged by the Playwright bot - agent run}