Might be a caching issue server-side. Though it has no business being an artist tag... O.o;;
Posted under General
No it was an honest mistake, there's a brand new artist tag (now moved to blink_(artist).) Lalaca is right, it's only not updating back to general because of the caching issue. I see this all the time on 3dbooru.
People occasionally don't check to see if a tag exists and assume they're the first one to upload it. In this case, someone uploaded with artist:blink then realized it was a general tag already in use and corrected it.