I am working with Advanced Custom Fields and I noticed that once I delete a field for a custom post type it will stay in the database. Is there a way that Wordpress can do a cleanup for everything that isn't being used? I read a little bit about cron jobs but to my understanding but I really couldn't see a way for a job to know what the site uses, it probably could only delete revisions of things. And that wouldn't solve the problem. I also think I could just uninstall the plugin and reinstall it. But that also isn't a realistic solution.