$ curl -s -o /dev/null -D - https://frenxi.com/http-headers-you-dont-expect/
    HTTP/1.1 200 OK
  Content-Type: text/html
  Content-Length: 47608
  Connection: keep-alive
  Last-Modified: Fri, 15 May 2020 01:35:43 GMT
  x-amz-server-side-encryption: AES256
  Accept-Ranges: bytes
  Server: AmazonS3
  Via: 1.1 ddaf46a95abcfc80e8eae76235e2127c.cloudfront.net (CloudFront), 1.1 37d64bca4c93552139fb3a85c9c4a119.cloudfront.net (CloudFront)
  Strict-Transport-Security: max-age=31536000; includeSubDomains
  X-Frame-Options: SAMEORIGIN
  X-XSS-Protection: 1; mode=block
  X-Content-Type-Options: nosniff
  X-hack: Like HTTP headers? Check this blog post https://frenxi.com/http-headers-you-dont-expect/
  X-Amz-Cf-Pop: SEA19-C2
  Date: Fri, 15 May 2020 04:48:24 GMT
  ETag: "194d54c969aad10b9c74ca6d591ae3e7"
  Cache-Control: public, must-revalidate, max-age=0
  Vary: Accept-Encoding
  X-Cache: RefreshHit from cloudfront
  X-Amz-Cf-Pop: SFO20-C1
  X-Amz-Cf-Id: J_OaNOGn_a8oZRQzKfe9spXbuDp-V-zhmlX1tQJSLNM1BD4EFTYERg==