Thread:Project:Support desk/find category of current page/reply

You mean as user on page itself or with a script/extension? For first: Simply look at the bottom of page, which categories listed in "categories" area. If the area isn't there, not categories set to this page :) You can see the categories in edit view, too. Simply search for term "[[Category" (in your language).

If you want to do that via code/script/extension, you can use getParentCategories of your Title-Instance (https://doc.wikimedia.org/mediawiki-core/master/php/html/classTitle.html#ad44b1db65e5e1ccafa71512f0014d43d) or better use getCategories of your WikiPage Instance (https://doc.wikimedia.org/mediawiki-core/master/php/html/classWikiPage.html#a7acdb0a992e0ff6c8c7053a5d6f83cc0).