**Reason**
[your rationale]
**To-do list**
- This task
-- [ ] Add maintainers of that extension as subscribers to this task (if they have no apparent Phabricator account, notify them on-wiki or via email if possible and note it here).
-- [x] Add Phabricator project #wikibase-quality as a tag for this task.
- On-wiki documentation
-- [ ] Archive documentation on `mediawiki.org` (https://www.mediawiki.org/wiki/Extension:WikibaseQuality): replace page contents with `{{TNT|Archived extension|3041990|reason=archive reasons, per [[phab:T205065]]}}`.
-- [ ] If documentation page was translatable, remove `<translate>`, visit Special:PageTranslation, and click "remove from translation" (if you don't have the translation administrator right, ask a [[ https://www.mediawiki.org/wiki/Special:ListUsers/translationadmin | user who does ]]).
-- [ ] ~~Archive Wikidata item associated with documentation page (provide URL) (remove nearly all statements, except `instance of (P31) = MediaWiki extension (Q6805426)`, which should add a qualifier `end time (P582) = the YYYY-MM-DD date that you decided to archive extension, generally per edit history`, change English (and other languages if possible) description to "archived MediaWiki extension" (and its translation)).~~
- Phabricator
-- [ ] Archive Phabricator project #wikibase-quality for the extension.
-- [ ] Mark all Phabricator tasks for the extension either Declined or Invalid (only if they are //not// also tagged as #wikibase-quality-constraints, per T205065#4994113).
-- [ ] Edit Phabricator project #wikibase-quality description for the extension with a link to this ticket.
- Translatewiki.net/translations
-- [ ] Remove from `translatewiki.net` (`groups/MediaWiki/mediawiki-extensions.txt`) (add #translatewiki.net project as a tag for this task).
- Configuration/tests/integrations/etc.
-- [ ] Remove from `mediawiki/extensions` (along with in `.gitmodules`).
-- [ ] Remove tests in [[ https://gerrit.wikimedia.org/g/integration/config | `integration/config` ]] (`zuul/layout.yaml`).
-- [ ] Remove manifest/other references from `mediawiki/vagrant` if they exist.
-- [ ] Remove from https://doc.wikimedia.org/cover-extensions/ if present (requires #continuous-integration-infrastructure shell user to delete directly from the server).
- Repositories
-- [ ] Empty repository leaving only the README indicating the repo is archived and referring to this task by URL.
-- [ ] Mark the repository read-only in Gerrit (Edit description to prepend "[ARCHIVED]" and append Task reference): https://gerrit.wikimedia.org/r/admin/projects/mediawiki/extensions/WikibaseQuality
-- [ ] Archive the diffusion repository for the extension/skin: (provide the Diffusion repository callsign or URL).
-- [ ] Delete the GitHub mirror: (provide GitHub repository URL).