User story: As an editor with a very large number of pages on my Watchlist, I want to remove a substantial percentage of them that I'm no longer interested in watching, so that it can be a more manageable size.

Many of Wikimedia's most active editors have developed extremely large watchlists (where 'large' means more than a few thousand pages, some as many as hundreds of thousands). It is impractical (and sometimes impossible - T41510) for these users to remove pages one-by-one to reduce the size of their watchlist back to a manageable number of pages.

One straightforward solution could be to build a simple tool that allows users to log in via OAuth and have pages removed from their watchlist according to some criteria they can set.

The tool could use the Watchlistraw API to retrieve all the pages on the user's watchlist, then go through page-by-page to see if meets the criteria they set, and remove it from their watchlist if so.

Criteria could include:

• Pages that are deleted and haven't existed in some period of time
• Pages the user hasn't edited in some period of time
• Pages the user has only ever made 1 edit to, where that edit is a revert