Extension:Replace Text - MediaWiki
www.mediawiki.org/wiki/Extension:Replace_Text
From the page
Saved with the link. Notes from 2007 to 2016 are mostly the page's own words, so this is probably an excerpt.
Replace Text is an extension to MediaWiki that provides a special page to allow administrators to do a global string find-and-replace on both the text and titles of the wiki's content pages.