I want to show some content from Sharepoint in IFRAME. From some research, I come to know that specific setting for X-FRAME-OPTIONS in HTTP Header prevents rendering in iframes. How can I use ALLOW-FROM option of X-FRAME-OPTIONS to allow this? Given, I am admin for the Sharepoint Server 2013.
According to this post you need to add a SharePoint 2013 specific tag to your ASPX page to disable the SharePoint 2013 default behavior of X-FRAME-OPTIONS.
The particular tag is:
and as far as I can see it is required on each and every ASPX page you want to allow. I personally haven't figured out yet how to disable it globally (sigh).