Feature summary:

A way to filter the table at Special:EditWatchlist to show only those items with a given set of labels, or with no label at all.

Use case(s):

When labelling items, it's useful to be able to quickly view items that are not yet labelled, or that have been given a particular label (or set of labels).

Benefits:

Adding labels will be easier.

Other info:

This was requested on mw:Help talk:Watchlist labels.