Seems on dozens of Wikimedia wikis (except Wikipedias) and translatewiki.net.
Try "all" and "none" buttons of these:
* [[ https://en.wikipedia.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | Wikipedia (Please Do Not directly type asdfg, it redirects to "Touch typing" article) ]]
* [[ https://en.wiktionary.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | Wiktionary ]]
* [[ https://en.wikibooks.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | Wikibooks ]]
* [[ https://en.wikinews.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | Wikinews ]]
* [[ https://en.wikiquote.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | Wikiquote ]]
* [[ https://en.wikisource.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | Wikisource ]]
* [[ https://en.wikiversity.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | Wikiversity ]]
* [[ https://en.wikivoyage.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | Wikivoyage ]]
* [[ https://meta.wikimedia.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | Meta-Wiki ]]
* [[ https://commons.wikimedia.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | Commons ]]
* [[ https://species.wikimedia.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | Wikispecies ]]
* [[ https://www.mediawiki.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | MediaWiki.org ]]
* [[ https://www.wikidata.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | MediaWiki.org ]]
* [[ https://outreach.wikimedia.org/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | Outreach Wiki ]]
* [[ https://translatewiki.net/w/index.php?title=Special:Search&search=asdfg&fulltext=Search&profile=advanced | Translatewiki.net ]]
and so on...