[[ https://gerrit.wikimedia.org/g/operations/mediawiki-config/+/a816755e12f793573a0da39d70990d7e068f35d0/wmf-config/InitialiseSettings.php#7825 | $wgVectorResponsive is only enabled on testwiki ]] and doesn't appear to be used elsewhere. As the configuration was introduced about four years ago, it seems unlikely to suddenly become popular and is most probably a good candidate for removal.
- All $wgVectorResponsive references from Vector are removed.
- All related and now unused code and resources in Vector are removed.
- All $wgVectorResponsive references from mediawiki-config are removed.
- Smoke test that a beta cluster page loads in Vector.