=== HTTP code : 200 ===

Response headers
================
HTTP/1.1 301 Moved Permanently
Server: awselb/2.0
Date: Mon, 29 Jul 2019 00:55:59 GMT
Content-Type: text/html
Content-Length: 150
Connection: close
Location: https://issuu.com:443/ssdp/docs/ssdp2012-program?mode=window&amp;backgroundColor=%23222222

HTTP/1.1 302 Found
Date: Mon, 29 Jul 2019 00:55:59 GMT
Content-Type: text/plain; charset=utf-8
Content-Length: 75
Connection: close
Set-Cookie: iutk=a1741f60b19b11e9b282004973737575; Max-Age=15552; Domain=issuu.com; Path=/; Expires=Mon, 29 Jul 2019 05:15:11 GMT
Location: /ssdp/docs/ssdp2012-program?backgroundColor=%23222222
Vary: Accept
X-Content-Type-Options: nosniff

HTTP/1.1 200 OK
Date: Mon, 29 Jul 2019 00:56:00 GMT
Content-Type: text/html; charset=utf-8
Content-Length: 80458
Connection: close
Set-Cookie: iutk=a1822920b19b11e988ea004973737575; Max-Age=315360; Domain=issuu.com; Path=/; Expires=Thu, 01 Aug 2019 16:31:59 GMT
ETag: W/&quot;13a4a-WYm3CqywV6ZRyDmTtj0FPgzS0VE&quot;
X-Content-Type-Options: nosniff

Request headers
================
HEAD /ssdp/docs/ssdp2012-program?backgroundColor=%23222222 HTTP/1.1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.102 Safari/537.36
Host: issuu.com
Accept: */*
Referer: https://ssdp.org
Connection: close


Link is valid.