I've tested on XWiki 16.2.0 with Hidden Pages set to Yes for Admin and indeed, these are filters related to the Setting Hidden Pages being OFF by default in previous XWiki versions, that's why they were not present.
However, the new behavior causes also custom filters related to {{Web Preferences}} for a page to be displayed (for ex after modifying a right on a page): !Web_Preferences_page.png|thumbnail!
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