Feature summary (what you would like to be able to do and where):
In the watchlist, if I unselect "Category changes", I should not see the HotCat changes.
Use case(s) (list the steps that you performed to discover that problem, and describe the actual underlying problem which you want to solve. Do not describe only a solution):
In my wp:en watchlist, if I have the "Category changes" selected, I can see all the additions of an article into a category. If I unselect it, I can't see these additions anymore, which is OK. But I still see the HotCat additions.
In my wp:fr watchlist if I have the "catégorisation de la page" unselected, I can see all the additions of an article into a category. If I select it, I can't see these additions anymore, which is OK. But I still see the HotCat additions.
Benefits (why should this be implemented?):
An HotCat change is an edit change, but it only consists in adding a category, so it should be considered a category change and be hidden if the "Category changes" is unselected, so the watchlist is not overflowed with non-real edit changes if not wanted. And often, many HotCat changes come together and when one has a bulky watchlist, it is a bit annoying.