After this you need to add this $wgExpandedLevelsOnCategoryPages = 10; to localsettings (it represents the expanding levels on category pages)
==== Fixes for sidebar ====
See https://www.mediawiki.org/w/index.php?title=Topic:Sde4gvisgd1ffcez&topic_showPostId=sdynp60mol2zsrsb#flow-post-sdynp60mol2zsrsb