User blog comment:Rappy 4187/Technical Update: February 22, 2017/@comment-26569706-20170225212532/@comment-126761-20170226025826

You can also use Special:EditWatchlist to make lots of changes at once. Or even Special:EditWatchlist/raw for really big bulk updates (note: if you have thousands of pages on your list, remove them in chunks - otherwise it gets a big unhappy).