Available from version 1.6.0
Called every time wikitext is added to the OutputPage, after it is parsed but before it is added.
Define function:
public static function onOutputPageBeforeHTML( OutputPage $out, &$text ) { ... }
Attach hook: In extension.json:
	"Hooks": {
		"OutputPageBeforeHTML": "MyExtensionHooks::onOutputPageBeforeHTML"
Called from: File(s): OutputPage.php
Interface: OutputPageBeforeHTMLHook.php

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


Use this hook at your own risk.

  • Not used for edit previews (bug 7050) until 1.11.0 (r25341).
  • Can cause infinite loops (see talk)
  • May fail under certain caching systems
  • Runs on every page load and page view, so increases overhead


  • $out: the OutputPage (object) to which wikitext is added
  • $text: the HTML text (string) that is being added