The HTTP X-Frame-Options header

The X-Frame-Options options header can be used to stop other websites opening your webpages inside a FRAME or IFRAME.

You can set it in server config, virtual hosts, .htaccess or HTML

Here is an HTML example

<!-- dont open this page in an iframe -->
<meta name="header" content="X-Frame-Options: DENY" >

And a server config example

# allow pages from this domain name to open pages in iframes, no one else
Header always append X-Frame-Options SAMEORIGIN

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