Search box in Commons categories of media files (Community Wishlist/W464)

Description

This is about including a search box for Commons categories on all Commons categories by default (or all that have more files than can be quickly glanced over or all checked).

Such a search box is included in c:Category:Our World in Data (contains many data graphics) – please click that link and use that search box to understand what this wish is about and how such a search box can be useful.

The search would search files also in the layers of subcategories so one doesn't need to go through all them manually. Or at least that would be one mode of it (there could be a dropdown with which to switch the mode from deepcategory to incategory which only searches files directly in the category).

A key problem is that some categories have grown large and contain offtopic categories. This is why related wish W397: In Commons category deepcategory view mode (wall of images), allow easily filtering offtopic subcats is the key blocker to implementing this wish. I think it may not be clear to users here that this is what solving that wish could enable.
For fixing the miscategorizations so that deepcat results all show ontopic results, both better enabling more users to use deepcat and W393: A way to see why a file is somewhere underneath a specific category (tool to show cat-path) seem needed or at least highly impactful.

Another issue is that for very large or deeply nested categories, the deepcategory search only shows partial results. The current search box uses the deepcategory search operator and I don't know of an alternative approach that could also be used but this wish is agnostic to how it's implemented technologically. Yet another challenge or issue is that one can't specify the tab that the search box should open and/or that it doesn't adjust it automatically (e.g. in a category like c:Category:Time-lapse videos it should not be 'Images' but 'Videos') – see phab:T404955.

There also is the gadget DeepcatSearch with which one can reach that search from the Tools dropdown.

Using categories for searching media can be very useful in many contexts and for many applications.

Assigned focus area

Unassigned

Type of wish

Feature request