Manual:$wgBreakFrames

Security: $wgBreakFrames
Break out of framesets. This can be used to prevent external sites from framing your site with ads.
Introduced in version:1.9.0 (r18220)
Removed in version:still in use
Allowed values:(boolean)
Default value:false

Details edit

Break out of framesets. This can be used to prevent external sites from framing your site. If set to "true" it will also prevent positive uses of frames.

Since MediaWiki 1.16.1, certain pages (like edit pages) automatically have frames broken by default to prevent clickjacking attacks.

If you set this configuration parameter to true you no longer need to configure X-Frame-Options on the level of your wiki's virtual host. DENY will be set.

See also edit