Manual:$wgXhtmlDefaultNamespace

Output: $wgXhtmlDefaultNamespace
Namespace to use when outputting in XHTML mode.
Introduced in version:1.9.0 (r18943)
Deprecated in version:1.22.0 (Gerrit change 63106; git #97caae59)
Removed in version:1.34.0 (Gerrit change 522570; git #a8d26127)
Allowed values:(string)
Default value:'http://www.w3.org/1999/xhtml' (defined in Setup.php )

Details

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What namespace to use when in XHTML mode. This is the xmlns attribute on the root ‎<html> element. When in HTML5 mode (default in recent MediaWiki), this setting is ignored.

See also

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