Manual:$wgHtml5

Output: $wgHtml5
Whether to output an HTML 5 doctype.
Introduced in version:1.16.0 (r53034)
Deprecated in version:1.22.0 (Gerrit change 63106; git #97caae59)
Removed in version:1.34.0 (Gerrit change 522570; git #a8d26127)
Allowed values:(boolean)
Default value:true

Details edit

Whether to output an HTML5 doctype. See HTML5 for more information.

If $wgWellFormedXml is set to "true", the markup will be constructed so it can still be processed as XML.

In order to allow the use of microdata attributes in wikitext, set $wgAllowMicrodataAttributes to "true".