Actual error message from MediaWiki's CentralAuth extension:
Use of User::makeGroupLinkWiki was deprecated in MediaWiki 1.29. [Called from GlobalUsersPager::getUserGroups in /srv/mediawiki/php-1.31.0-wmf.10/extensions/CentralAuth/includes/specials/SpecialGlobalUsers.php at line 270]
We have to replace User::makeGroupLinkWiki() by the equivalent methods on the [[ https://doc.wikimedia.org/mediawiki-core/master/php/classUserGroupMembership.html | UserGroupMembership ]] class.