Board Thread:Support Requests - Getting Technical/@comment-27101389-20190317015903

On Sly Cooper Wiki, Category:Concept Art apparently has 5 items in it, but as you can see, there's no items listed on the page. The page is currently a redirect to the properly capitalized name; otherwise, if the page were deleted, then it would appear in Special:WantedCategories due to the 5 "ghost" items in the category.

I tested it out, and apparently when a category is inserted in a forum/message wall post, it adds that post to the category, but only increases the item count (the post does not show up on the list of items). This is what I think is happening here. I've tried using Special:WhatLinksHere, but it will not show me anything. Is there a way to find out what's in this category? 