Soft 404
A page that tells visitors it does not exist (or has nothing on it) but answers with a 200 "OK" status instead of 404.
Search engines detect soft 404s and treat them as errors, reporting them in Search Console. They waste crawling on pages that should not be indexed. A missing page should return 404 or 410; an empty search or category page should be noindexed or not linked.
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