Blocked: this page cannot be embedded

gist.github.com · 200 OK · 220 ms

gist.github.com sends CSP frame-ancestors 'none'. Every browser will refuse to show it in a frame.

Framing rules

  • X-Frame-Options: denyignored

    Browsers ignore X-Frame-Options here, because CSP frame-ancestors is set and wins.

  • frame-ancestors 'none'deny

    frame-ancestors 'none' stops every site from showing the page in a frame.

  • Set-Cookie × 3warning

    None of the 3 cookies go into a cross-site frame (_gh_sess, _octo, logged_in): a cookie needs SameSite=None; Secure for that. A login or session inside the frame can fail.

  • Cross-Origin-Resource-Policyabsent

    Not sent. A cross-origin page with Cross-Origin-Embedder-Policy: require-corp cannot embed it.

Raw response headers

HTTP 200 OK
cache-control: max-age=0, private, must-revalidate
cf-cache-status: DYNAMIC
cf-ray: a579bb3c1c4d3524-CMH
connection: close
content-security-policy: default-src 'none'; base-uri 'self'; child-src github.githubassets.com github.com/assets-cdn/worker/ github.com/assets/ gist.github.com/assets-cdn/worker/; connect-src 'self' uploads.github.com www.githubstatus.com collector.github.com raw.githubusercontent.com api.github.com github-cloud.s3.amazonaws.com github-production-repository-file-5c1aeb.s3.amazonaws.com github-production-upload-manifest-file-7fdce7.s3.amazonaws.com github-production-user-asset-6210df.s3.amazonaws.com *.rel.tunnels.api.visualstudio.com wss://*.rel.tunnels.api.visualstudio.com github.githubassets.com objects-origin.githubusercontent.com copilot-proxy.githubusercontent.com proxy.individual.githubcopilot.com proxy.business.githubcopilot.com proxy.enterprise.githubcopilot.com *.actions.githubusercontent.com wss://*.actions.githubusercontent.com productionresultssa0.blob.core.windows.net productionresultssa1.blob.core.windows.net productionresultssa2.blob.core.windows.net productionresultssa3.blob.core.windows.net productionresultssa4.blob.core.windows.net productionresultssa5.blob.core.windows.net productionresultssa6.blob.core.windows.net productionresultssa7.blob.core.windows.net productionresultssa8.blob.core.windows.net productionresultssa9.blob.core.windows.net productionresultssa10.blob.core.windows.net productionresultssa11.blob.core.windows.net productionresultssa12.blob.core.windows.net productionresultssa13.blob.core.windows.net productionresultssa14.blob.core.windows.net productionresultssa15.blob.core.windows.net productionresultssa16.blob.core.windows.net productionresultssa17.blob.core.windows.net productionresultssa18.blob.core.windows.net productionresultssa19.blob.core.windows.net productionresultssa30.blob.core.windows.net productionresultssa31.blob.core.windows.net productionresultssa32.blob.core.windows.net github-production-repository-image-32fea6.s3.amazonaws.com github-production-release-asset-2e65be.s3.amazonaws.com insights.github.com wss://alive.github.com wss://alive-staging.github.com api.githubcopilot.com api.individual.githubcopilot.com api.business.githubcopilot.com api.enterprise.githubcopilot.com wss://production-copilot-host.webpubsub.azure.com wss://production-copilot-host-centralus.webpubsub.azure.com wss://production-copilot-host-centralus-02.webpubsub.azure.com wss://production-copilot-host-westus.webpubsub.azure.com wss://production-copilot-host-westus3.webpubsub.azure.com api.github.com/cmc_internal/api/; font-src github.githubassets.com; form-action 'self' github.com gist.github.com copilot-workspace.githubnext.com objects-origin.githubusercontent.com; frame-ancestors 'none'; frame-src viewscreen.githubusercontent.com notebooks.githubusercontent.com; img-src 'self' data: blob: github.githubassets.com media.githubusercontent.com camo.githubusercontent.com identicons.github.com avatars.githubusercontent.com private-avatars.githubusercontent.com github-cloud.s3.amazonaws.com objects.githubusercontent.com release-assets.githubusercontent.com secured-user-images.githubusercontent.com user-images.githubusercontent.com private-user-images.githubusercontent.com opengraph.githubassets.com repository-images.githubusercontent.com marketplace-screenshots.githubusercontent.com copilotprodattachments.blob.core.windows.net/github-production-copilot-attachments/ github-production-user-asset-6210df.s3.amazonaws.com customer-stories-feed.github.com spotlights-feed.github.com explore-feed.github.com *.googleusercontent.com objects-origin.githubusercontent.com *.githubusercontent.com; manifest-src 'self'; media-src github.com user-images.githubusercontent.com secured-user-images.githubusercontent.com private-user-images.githubusercontent.com github-production-user-asset-6210df.s3.amazonaws.com gist.github.com github.githubassets.com; script-src github.githubassets.com 'sha256-6AKuI+cDd1MoUL1u4eqrA9PXmnPAkOB4h7421hPUUm0='; style-src 'unsafe-inline' github.githubassets.com; upgrade-insecure-requests; worker-src github.githubassets.com github.com/assets-cdn/worker/ github.com/assets/ gist.github.com/assets-cdn/worker/
content-type: text/html; charset=utf-8
date: Mon, 09 Nov 2026 03:29:08 GMT
etag: W/"809a13f8d6a35e7f6f816dc50c83e15f"
referrer-policy: origin-when-cross-origin, strict-origin-when-cross-origin
server: cloudflare
strict-transport-security: max-age=31536000; includeSubdomains; preload
transfer-encoding: chunked
vary: X-PJAX, X-PJAX-Container, Turbo-Visit, Turbo-Frame, X-Requested-With, X-GitHub-Client-Version,Accept-Encoding, Accept, X-Requested-With
x-content-type-options: nosniff
x-frame-options: deny
x-github-edge-region: iad
x-github-request-id: 3290:3FE245:4F0A4D:67B9C6:6AF13E04
x-xss-protection: 0
set-cookie: _gh_sess=…; path=/; HttpOnly; secure; SameSite=Lax
set-cookie: _octo=…; expires=Tue, 09 Nov 2027 03:29:08 GMT; domain=.github.com; path=/; secure; SameSite=Lax
set-cookie: logged_in=…; expires=Tue, 09 Nov 2027 03:29:08 GMT; domain=.github.com; path=/; HttpOnly; secure; SameSite=Lax

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