As part of the removal of the dual mode Linter recordLinJob code and user interface and report generator code to utilize the added namespace and tag and template fields, 3rd party wikis need to run the maintenance scripts during the update/upgrade cycle. The four configuration variables used during the rollout of the database updates and feature enablements was useful for WMF deployment but needs to be removed to reduce code clutter.
The steps to accomplish this were discussed in Slack by:
CScott: "The Linter extension has some maintenance scripts that should be run before the upgrade to 1.43 (configuration variables going away, etc)"
JamesF: "Yes, if you can add it to the DatabaseUpdater with addExtensionUpdate() (docs) that should work well enough for anyone except people that don't run update.php, like Wikimedia production, which you'll have to do manually."
JamesF: "Here's an example from Wikibase: https://gerrit.wikimedia.org/g/mediawiki/extensions/Wikibase/+/HEAD/client/includes/Hooks/LoadExtensionSchemaUpdatesHookHandler.php"