**Reason**:
The CryoKey has not received any code update for the last 5 years beside the usual robot maintenance. It seems to be a system with a hardware key for authentication.
https://wikiapiary.com/wiki/Extension:CryoKey shows only one public deployment. It is the company wiki and is at version 1.20.
The extension has not been updated to use AuthManager introduced in MediaWiki 1.27: T110452
- [x] Archive documentation on `mediawiki.org` ( https://www.mediawiki.org/wiki/Extension:CryoKey )
- [ ] Remove from `mediawiki/extensions` ( along with in `.gitmodules`)
- [ ] Remove tests in `integration/config` ( `zuul/layout.yaml` )
- [ ] Remove from `translatewiki` ( `groups/MediaWiki/mediawiki-extensions.txt`)
- [ ] Remove manifest/other references from `mediawiki/vagrant` if they exist
- [ ] Empty repository and add a OBSOLETE file.
- [ ] Archive the extension's diffusion repository: rECRK
- [ ] Mark the repository read-only in Gerrit: https://gerrit.wikimedia.org/r/#/admin/projects/mediawiki/extensions/CryoKey
- [ ] Delete the GitHub mirror: https://github.com/wikimedia/mediawiki-extensions-CryoKey