docs(network): explain how request interception relates to the network stack - #42646
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Pavel Feldman (pavelfeldman) merged 1 commit intoSep 14, 2026
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…k stack References: microsoft#42620
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Test results for "tests 1"5 flaky51528 passed, 1246 skipped Merge workflow run. |
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Test results for "MCP"1 failed 8347 passed, 1376 skipped Merge workflow run. |
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Hi, I'm the Playwright bot and I took a look at the CI failures here. 🟢 The one failure isn't caused by this PRThis is a docs-only change (a "How request interception works" section in DetailsPre-existing flake / infra
Flaky (no triage needed) — from the
Triaged by the Playwright bot - agent run |
Yury Semikhatsky (yury-s)
approved these changes
Sep 10, 2026
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| ### Headers owned by the network stack | ||
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| Some headers are attached by the network stack right before the request is sent: `Cookie`, `Host`, `Accept-Encoding`, `Content-Length`, `Sec-Fetch-*` and a few others. This is a security boundary: an `HttpOnly` cookie, for example, is never exposed to the page. Since the route handler runs before that step, these headers are not reliably present in [`method: Request.headers`] or [`method: Request.allHeaders`], and they cannot be overridden. A `cookie` header passed to [`method: Route.continue`] is ignored in favor of the browser's cookie store. |
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Yet Cookie header is available on intercepted request, we might want to clarify that to avoid confusion.
Pavel Feldman (pavelfeldman)
merged commit Sep 14, 2026
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Summary
Sec-Fetch-*, ...) are not visible or overridable in the handler but are visible on the response; redirects are followed by the browser and the handler runs once per chain; fulfilling with a redirect is not supported.mermaidcode blocks in doclint.References #42620