recently i also came across this problem. i don’t mind the unused data per se but that it turns up in search results is a bummer. a lot of wordpress sites seem to suffer from this since i find a lot of weird search results on various wordpress sites i experimented with. 🙂
what is the current status of this and the cleanup plugins that some users did?
wouldn’t a simple solution be to just delete all custom fields of a post on save_post (priority 1) and acf will store the currently used ones again afterwards anyway? a batch job could walk through all posts and resave them.
someone mentioned a potential issue with clone fields but i never used them and don’t even know what they are. 🙂
