I've tried this with several character tags.
a standard character tag search (kurugaya_yuiko) works.
But searching "kurugaya_yuiko rating:s" or "kurugaya_yuiko -rating:s", all I get is the "nobody here but us chickens!" error message.
The same happens when I attempt a search with the other rating tags.
All cookies and scripts are enabled for danbooru on my browser (Firefox), if that's any useful information.
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