to Special:MyPage/common.js. Then follow the instructions for purging your browser cache. You should now see an "Import watchlist" link in the top-right corner of Special:Watchlist. Click it. Choose a project from the dropdown menu. Enter a language code ("en" for English). A language code is not needed for the Commons, Meta-Wiki, or MediaWiki. Then click the Special:Preferences link in the sentence below the project dropdown menu. That link will go to the Special:Preferences page of the project you selected in the previous step. Go to the watchlist tab, and copy the watchlist token. Then paste the token in the form on Special:Watchlist to the left of the "Import watchlist" button. Then click that "Import watchlist" button to the right of the form. You will then see the added watchlist above the Wikipedia watchlist. The added watchlist can be expanded, collaped, or removed. If removed, you can add it back by repeating the above steps. You can add multiple watchlists by repeating the above steps.