Available from version 1.19.0 (r94259, codereview)
Removed in version 1.29.0
called when determining if a page is a wikitext or should be handled by seperate handler (via ArticleViewCustom
Define function:
public static function onTitleIsWikitextPage( $title, &$result ) { ... }
Attach hook: In extension.json:
	"Hooks": {
		"TitleIsWikitextPage": "MediaWiki\\Extension\\MyExtension\\Hooks::onTitleIsWikitextPage"
Called from: File(s): Title.php
Interface: TitleIsWikitextPageHook.php

For more information about attaching hooks, see Manual:Hooks .
For examples of extensions using this hook, see Category:TitleIsWikitextPage extensions.