=== HTTP code : 200 ===

Response headers
================
HTTP/2 200 
expires: Sat, 01 Jan 2000 00:00:00 GMT
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pragma: no-cache
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access-control-expose-headers: X-FB-Debug, X-Loader-Length
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vary: Origin
vary: Accept-Encoding
cache-control: private, no-cache, no-store, must-revalidate
access-control-allow-origin: https://developers.facebook.com
access-control-allow-methods: OPTIONS
content-type: text/html; charset=&quot;utf-8&quot;
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date: Mon, 15 Apr 2019 00:13:23 GMT

Request headers
================
HEAD /docs/plugins/like-box-for-pages HTTP/2
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Link is valid.