fix(chromium): report 204 subresource responses as finished

[Yury Semikhatsky (yury-s)]

Summary

• Chromium reports a 204 response via Network.loadingFailed with net::ERR_ABORTED; treat it as finished like other browsers do.
• page.goto to a 204 URL still fails in Chromium: the error comes from the errorText in the Page.navigate command result, not from the network events.

Fixes #42786

[Pavel Feldman (pavelfeldman)]

isNavigationRequest is a wrong differentiator here, listener to all network on a context should treat all 204s equally.

[Yury Semikhatsky (yury-s)]

removed, it's not necessary, Page.navigate already has the error.

[github-actions]

Test results for "tests 1"

7 flaky

⚠️ [chromium-library] › library/browsercontext-page-event.spec.ts:173 › should work with Ctrl-clicking `@frozen-time-library-chromium-linux`
⚠️ [chromium-library] › library/video.spec.ts:762 › screencast › should work with video+trace `@frozen-time-library-chromium-linux`
⚠️ [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:521 › screencast › should capture static page in persistent context Radoslav Kirilov (@smoke) `@chromium-ubuntu-22.04-node24`
⚠️ [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`

52038 passed, 1244 skipped

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Merge workflow run.

[github-actions]

Test results for "MCP"

3 failed
❌ [firefox] › mcp/cli-devtools.spec.ts:140 › request* and response* commands support --filename @mcp-windows-latest-firefox
❌ [firefox] › mcp/cli-mouse.spec.ts:38 › mousewheel @mcp-windows-latest-firefox
❌ [firefox] › mcp/cli-session.spec.ts:54 › idle timeout shuts the session down @mcp-windows-latest-firefox

8689 passed, 1474 skipped

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Merge workflow run.

[github-actions]

🟢 All three failures are known flakes — the PR is clear

Hi, I'm the Playwright bot and I triaged the failing CI run.

The three reds are all [firefox] › mcp/* on mcp-windows-latest-firefox. This PR only changes Chromium's crNetworkManager.ts plus a Chromium-gated assertion in page-event-request.spec.ts, so it can't reach the Firefox MCP CLI path. Each test also flips verdict on unrelated SHAs, including pushes to main.

Details

Pre-existing flake / infra

• [firefox] › mcp/cli-session.spec.ts:54 › idle timeout shuts the session down — the worst of the three. On this bot it failed 43 of 137 runs (31%) and passed the other 94, across 42 distinct SHAs. Recent reds include docs(cli): do not suggest generating test scenarios in parallel #42833 (478ae0a1), fix(firefox): preserve response header field boundaries #42832 (f61c51d2) and several main pushes (b8627f95, f14e9f5c, dc82cd77) from the same afternoon as this run. A timing-sensitive idle-timeout test on a Windows runner, unrelated to network event handling.

• [firefox] › mcp/cli-mouse.spec.ts:38 › mousewheel — failed 10 of 701 runs (1.4%) on this bot, 10 distinct SHAs, e.g. Fix spelling of restoring in credentials docs #42718 (d979f021), Revert "fix(mcp): drop the backend after browser_close with a shared browser" #42492 (c87c38e9), fix(tracing): allow restarting tracing after a failed stop #42425 (37de6670), and main pushes 18205280 and 858526b3.

• [firefox] › mcp/cli-devtools.spec.ts:140 › request* and response* commands support --filename — failed 4 of 701 runs (0.6%) on this bot, on fix(test): support multiple contexts with --debug=cli #42503 (7df53e86), feat(locator): introduce locator.visible() #42479 (5cc92193) and chore: remove experimental component testing #42168 (39db46e8).

Scope check

crNetworkManager.ts is Chromium-only — Network.loadingFailed with net::ERR_ABORTED never reaches Firefox, which routes through ffNetworkManager.ts. The test change is in a Chromium-specific expectation. Nothing in the diff is shared with the MCP CLI surface these three tests exercise.

Counts are from the aggregated CI results database (2014 runs), refreshed with the last 3 days before querying.

_{Triaged by the Playwright bot - agent run}