Typing into target category input, when trying to search for new categories, always fails with following JS error:
TypeError: this.categoryWidget.getCategories is not a function at CategoryInputWidget.ve.ui.MWCategoryInputWidget.getLookupMenuOptionsFromData (http://localhost/core/extensions/VisualEditor/modules/ve-mw/ui/widgets/ve.ui.MWCategoryInputWidget.js?8f79f:124:44) at CategoryInputWidget.<anonymous> (http://localhost/core/resources/lib/oojs-ui/oojs-ui-widgets.js?106e3:877:15) at mightThrow (http://localhost/core/load.php?debug=true&lang=en&modules=jquery%2Cmediawiki%7Cmediawiki.base&only=scripts&skin=vector&version=02igl38:3583:29) at process (http://localhost/core/load.php?debug=true&lang=en&modules=jquery%2Cmediawiki%7Cmediawiki.base&only=scripts&skin=vector&version=02igl38:3651:12) undefined