Hello!
Today I've learned that an hidden category (using __HIDDENCAT__) is just a page with a certain property in the `page_props` database table. To be precise, it should have 'pp_propname' => 'hiddencat'.
https://doc.wikimedia.org/mediawiki-core/master/php/WikiPage_8php_source.htm... https://www.mediawiki.org/wiki/Manual:Page_props_table
Having said that:
1. Why the hell in my personal MediaWiki database I have '68696464656e636174' as 'pp_propername' value (instead of the expected 'hiddencat' value)? 2. What does '68696464656e636174' mean? 3. Why does it work as expected? 3.1 Are there magic/obscure/evil lines of code behind the database abstraction layer?
Yes, I admit that I'm using MediaWiki 1.27.3 but yes, my local WikiPage.php looks exactly as the linked documentation.
Thanks for this clarification :D