**Reason**: Top item on http://korma.wmflabs.org/browser/gerrit_review_queue.html
No luck getting feedback in https://gerrit.wikimedia.org/r/#/c/184825/
Sent emails to maintainer on 09 May 2016 and 15 Jun 2016, no reply.
https://www.mediawiki.org/wiki/Extension:WikiTwidget
Follow https://www.mediawiki.org/wiki/Gerrit/Inactive_projects
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- [x] Archive documentation on `mediawiki.org`: http://mediawiki.org/wiki/Extension:WikiTwidget
- [x] Remove from `mediawiki/extensions` / `mediawiki/skins` ( along with in `.gitmodules`)
- [x] Remove tests in `integration/config` ( `zuul/layout.yaml` )
- [x] Remove from `translatewiki` ( `groups/MediaWiki/mediawiki-extensions.txt` )
- [ ] Empty repository and add a OBSOLETE file.
- [ ] Archive the extension's diffusion repository: rEWTW
- [ ] Mark the repository read-only in Gerrit: https://gerrit.wikimedia.org/r/#/admin/projects/mediawiki/extensions/WikiTwidget