This is a comment on Changing a Categorie of a page after it has been created, posted by WikiAdmin at 04.07.2020 12:08
Is the selected category a sub-category? If so then the parent category get automatically selected along with the sub-category, regardless if the parent-category is not selected in the form. This behavior was back-ported along with to category handler. This is of course not consistent with the selection made in the form. We can change this behavior so it selects only the chosen categories.