E.g. https://pl.wikipedia.org/wiki/AC?action=info&uselang=en says there are 3 "Subpages of this page" - but subpages are disabled in main NS using $wgNamespacesWithSubpages. These are regular page titles that happen to start with "AC/".
Version: unspecified
Severity: normal
URL: https://pl.wikipedia.org/wiki/AC?action=info&uselang=en