Administrative Details

In the 1.26 version (https://www.upwork.com/leaving?ref=https%3A%2F%2Fgithub.com%2Fwikimedia%2Fmediawiki-extensions-CategoryTree%2Ftree%2FREL1_26) you need to go to extensions/CategoryTree/CategoryPageSubclass.php at line 39 repalce "global $wgRequest;" with global $wgRequest, $wgExpandedLevelsOnCategoryPages; if (!$wgExpandedLevelsOnCategoryPages){ $wgExpandedLevelsOnCategoryPages = 0; } and on few lines below replace $this->children[] = $tree->renderNodeInfo( $title, $cat); with $this->children[] = $tree->renderNodeInfo( $title, $cat, $wgExpandedLevelsOnCategoryPages ); Or you can directly copy this file completely from test.

After this you need to add this $wgExpandedLevelsOnCategoryPages = 10; to localsettings (it represents the expanding levels on category pages)