As part of {T187716}, they have been undeployed. Since they are extremely Wikimedia specific, no point in keeping them around.
**To-do list**
- On-wiki documentation
-- [ ] Archive documentation on `mediawiki.org` (https://www.mediawiki.org/wiki/Extension:ZeroBanner and https://www.mediawiki.org/wiki/Extension:ZeroPortal): replace page contents with `{{TNT|Archived extension|last revision id before archiving|reason=archive reasons, per [[phab:T227731]]}}` include a link to this task in the `reason` parameter.
-- [ ] 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 ]]).
-- [ ] Update Wikidata item associated with documentation page
--- [ ] add statement `Abandonware (Q281039)` to `instance of (P31)` together with qualifier `start time (P580)` = the YYYY-MM-DD (date that you decided to archive extensions generally per edit history)
--- [ ] add qualifier `end time (P582)` = the YYYY-MM-DD (same date as above) to `instance of (P31) = MediaWiki extension (Q6805426)`
- Phabricator
-- [ ] Archive Phabricator projects #ZeroBanner and #ZeroPortal for the extensions.
-- [ ] Mark all Phabricator tasks for the extensions either Declined or Invalid.
-- [ ] Edit Phabricator project #ZeroBanner and #ZeroPortal description for the extensions 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` (https://phabricator.wikimedia.org/source/mediawiki-vagrant/browse/master/puppet/modules/role/manifests/zero.pp).
- 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/plugins/gitiles/mediawiki/extensions/ZeroBanner/ and https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/extensions/ZeroPortal/).
-- [ ] Archive the diffusion repository for the extensions: (rEZPO and rEZBA).
-- [ ] Delete the GitHub mirror: (https://github.com/wikimedia/mediawiki-extensions-ZeroPortal and https://github.com/wikimedia/mediawiki-extensions-ZeroBanner).