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Category:Entries with template subst detritus
Working cat for User:AutoFormat, tags entries that have detritus (flotsam, leftovers from template substitution). You needn't worry about this cat. If you do clean anything up, please doc at User talk:AutoFormat so we can see what is being found.
AF may be given rules to deal with (most) of these, and then re-process them.
Cat is hidden.