If you use Firefox, there is a user script you can install called Watchlist sorter.
This script sorts your watchlistbynamespace, and adds spaces within each entry. This makes the watchlist much easier to read.
To install the script, copy/paste the following line into your your common.js page. This will install the script across all your skins.
importScript("User:The Transhumanist/WatchlistSorter.js");
Note: After saving, you have to Bypass your cache. To do this in Firefox, hold down the ⇧ Shift key while clicking Reload (or press Ctrl+⇧ Shift+R). Or, you may have to {{purge}} the Wikipedia server cache.
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