HeaderAudit
A

developer.mozilla.org

Score 90/100 · scanned 2026-08-04

Content-Security-Policy

developer.mozilla.org sends an enforcing CSP. It is nonce-based.

default-src 'self'; script-src 'report-sample' 'self' 'wasm-unsafe-eval' assets.codepen.io production-assets.codepen.io https://js.stripe.com transcend-cdn.com 'sha256-XNBp89FG76amD8BqrJzyflxOF9PaWPqPqvJfKZPCv7M=' 'sha256-YCNoU9DNiinACbd8n6UPyB/8vj0kXvhkOni9/06SuYw=' 'sha256-PZjP7OR6mBEtnvXIZfCZ5PuOlxoDF1LDZL8aj8c42rw='; script-src-elem 'report-sample' 'self' 'wasm-unsafe-eval' assets.codepen.io production-assets.codepen.io https://js.stripe.com transcend-cdn.com 'sha256-XNBp89FG76amD8BqrJzyflxOF9PaWPqPqvJfKZPCv7M=' 'sha256-YCNoU9DNiinACbd8n6UPyB/8vj0kXvhkOni9/06SuYw=' 'sha256-PZjP7OR6mBEtnvXIZfCZ5PuOlxoDF1LDZL8aj8c42rw='; style-src 'report-sample' 'self' 'unsafe-inline' transcend-cdn.com; object-src 'none'; base-uri 'self'; connect-src 'self' developer.allizom.org bcd.developer.allizom.org bcd.developer.mozilla.org updates.developer.allizom.org updates.developer.mozilla.org https://incoming.telemetry.mozilla.org https://observatory-api.mdn.allizom.net https://observatory-api.mdn.mozilla.net telemetry.transcend.io telemetry.us.transcend.io transcend-cdn.com https://api.github.com/search/issues https://api.stripe.com; font-src 'self'; frame-src 'self' mdn.github.io *.mdnplay.dev *.mdnyalp.dev *.play.test.mdn.allizom.net https://v2.scrimba.com https://scrimba.com jsfiddle.net www.youtube-nocookie.com codepen.io survey.alchemer.com https://js.stripe.com; img-src 'self' data: *.githubusercontent.com *.gravatar.com mozillausercontent.com firefoxusercontent.com profile.stage.mozaws.net profile.accounts.firefox.com developer.mozilla.org mdn.dev wikipedia.org upload.wikimedia.org https://mdn.github.io/shared-assets/ https://mdn.dev/; manifest-src 'self'; media-src 'self' archive.org videos.cdn.mozilla.net https://mdn.github.io/shared-assets/; child-src 'self'; worker-src 'self';
DirectiveSources
default-src'self'
script-src'report-sample' 'self' 'wasm-unsafe-eval' assets.codepen.io production-assets.codepen.io https://js.stripe.com transcend-cdn.com 'sha256-XNBp89FG76amD8BqrJzyflxOF9PaWPqPqvJfKZPCv7M=' 'sha256-YCNoU9DNiinACbd8n6UPyB/8vj0kXvhkOni9/06SuYw=' 'sha256-PZjP7OR6mBEtnvXIZfCZ5PuOlxoDF1LDZL8aj8c42rw='
script-src-elem'report-sample' 'self' 'wasm-unsafe-eval' assets.codepen.io production-assets.codepen.io https://js.stripe.com transcend-cdn.com 'sha256-XNBp89FG76amD8BqrJzyflxOF9PaWPqPqvJfKZPCv7M=' 'sha256-YCNoU9DNiinACbd8n6UPyB/8vj0kXvhkOni9/06SuYw=' 'sha256-PZjP7OR6mBEtnvXIZfCZ5PuOlxoDF1LDZL8aj8c42rw='
style-src'report-sample' 'self' 'unsafe-inline' transcend-cdn.com
object-src'none'
base-uri'self'
connect-src'self' developer.allizom.org bcd.developer.allizom.org bcd.developer.mozilla.org updates.developer.allizom.org updates.developer.mozilla.org https://incoming.telemetry.mozilla.org https://observatory-api.mdn.allizom.net https://observatory-api.mdn.mozilla.net telemetry.transcend.io telemetry.us.transcend.io transcend-cdn.com https://api.github.com/search/issues https://api.stripe.com
font-src'self'
frame-src'self' mdn.github.io *.mdnplay.dev *.mdnyalp.dev *.play.test.mdn.allizom.net https://v2.scrimba.com https://scrimba.com jsfiddle.net www.youtube-nocookie.com codepen.io survey.alchemer.com https://js.stripe.com
img-src'self' data: *.githubusercontent.com *.gravatar.com mozillausercontent.com firefoxusercontent.com profile.stage.mozaws.net profile.accounts.firefox.com developer.mozilla.org mdn.dev wikipedia.org upload.wikimedia.org https://mdn.github.io/shared-assets/ https://mdn.dev/
manifest-src'self'
media-src'self' archive.org videos.cdn.mozilla.net https://mdn.github.io/shared-assets/
child-src'self'
worker-src'self'

Headers sent

HeaderValue
strict-transport-securitymax-age=63072000
x-frame-optionsDENY
x-content-type-optionsnosniff
referrer-policystrict-origin-when-cross-origin
serverGoogle Frontend

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