Outside Mainland China
$ curl -I https://github.com/programthink/zhao/issues/38
HTTP/1.1 200 OK
Server: GitHub.com
Date: Mon, 22 Jan 2018 04:17:56 GMT
Content-Type: text/html; charset=utf-8
Status: 200 OK
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Expect-CT: max-age=2592000, report-uri="https://api.github.com/_private/browser/errors"
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Inside Mainland China
$ curl -I https://github.com/programthink/zhao/issues/38
HTTP/1.1 451
Date: Mon, 22 Jan 2018 04:18:47 GMT
Content-Type: text/html; charset=utf-8
Server: GitHub.com
Status: 451
Cache-Control: no-cache
Vary: X-PJAX
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X-Request-Id: 4051e21a2f76143e6092e967ddfee9ca
X-Runtime: 0.050599
Expect-CT: max-age=2592000, report-uri="https://api.github.com/_private/browser/errors"
Content-Security-Policy: default-src 'none'; base-uri 'self'; block-all-mixed-content; child-src render.githubusercontent.com; connect-src 'self' uploads.github.com status.github.com collector.githubapp.com api.github.com www.google-analytics.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 wss://live.github.com; font-src assets-cdn.github.com; form-action 'self' github.com gist.github.com; frame-ancestors 'none'; img-src 'self' data: assets-cdn.github.com identicons.github.com collector.githubapp.com github-cloud.s3.amazonaws.com *.githubusercontent.com; media-src 'none'; script-src assets-cdn.github.com; style-src 'unsafe-inline' assets-cdn.github.com
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X-Content-Type-Options: nosniff
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