To build the list of dropdowns used to move a category on course/manage.php, coursecat::make_categories_list is called once per category.

The only difference is to specify the current category so that it is not included in the array. This leads to $categorycount calls to coursecat::make_categories_list() with almost identical data.

We could either use a MUC or static cache in print_category_edit() to only call make_categories_list once, or improve coursecat::make_categories_list() to return the cached copy earlier somehow.