Manual:$wgTextModelsToParse

Content handlers and storage: $wgTextModelsToParse
Determines which types of text are parsed as wikitext.
Introduced in version:1.21.0 (Gerrit change 28507; git #8b568be5)
Removed in version:Still in use
Allowed values:Content models, which are defined with the ContentHandler .
Default value:
[
	CONTENT_MODEL_WIKITEXT, // Just for completeness, wikitext will always be parsed.
	CONTENT_MODEL_JAVASCRIPT, // Make categories etc work, people put them into comments.
	CONTENT_MODEL_CSS, // Make categories etc work, people put them into comments.
];

Details

This does not imply that these kinds of texts are also rendered as wikitext, it only means that links, magic words, etc will have the effect on the database they would have on a wikitext page.