This week's 1.42.0-wmf.20 version of MediaWiki is blocked[0], and 1.42.0-wmf.19 may require a Monday rollback, which is a situation we hope to avoid. We can't proceed until the following issue is resolved: * T336504 - Transcluding Special:Prefixindex can force the default skin - https://phabricator.wikimedia.org/T336504 For context, see the Village pump discussion linked here: * https://phabricator.wikimedia.org/T336504#9572477 Once this issue is resolved, the train can proceed normally for the week. Thank you for any help! -- Your designated sacrificial train victims [0]. https://phabricator.wikimedia.org/T354438