It would be great and really, really helpful to patrollers if recent changes could be filtered by categories (with an option to include subcategories). So far something like that was possible only with an external tool (tools.wmflabs.org/erwin85/relatedchanges.php) but has not been working since a month ago (and it's not the first time it's down). Something that can be so useful IMO should be implemented in the MediaWiki code.
I tried to search but didn't find similar talks about it.