As category support is added to Recent Changes filters (T163433), research shows that users lack clarity about whether those would include sub-categories. Since adding all sub-categories automatically may be technically too complex, an alternative could be to surface the sub-categories as users add new categories. That would help to (a) confirm that these are not added and help with (b) the discovery of categories of interest for the user.
The mockups below illustrate a possible execution of the idea:
- The user selects a category
- Sub-categories are suggested (suggestions are only shown for one category at a time)
- Selecting one sub-category or the option to view more leads to a listing of the sub-categories.
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The diagram below illustrated the different workflows in more detail:
