I was trying to watch a talk page without watching the corresponding subject page (which, I have been informed, is not currently supported). If I add just the talk page Talk:Q42 on [[Special:EditWatchlist/raw]], the message is:
Your watchlist has been updated. 1 title was added:
- Talk:Q42 (talk)
But in fact Q42, both subject and talk, have been added, and opening [[Special:EditWatchlist/raw]] again shows that the actual added entry is just Q42. If I then change that to Talk:Q42 (i. e., the content is the same as with my previous edit), the message is:
Your watchlist has been updated. 1 title was added:
- Talk:Q42 (talk)
1 title was removed:
- Q42 (talk)
But in fact, the watchlist again contains Q42.
The behavior seems to be more or less intended (if you don’t want to support watching talk pages independently of subject pages), but the messages misleadingly suggest that this might actually be supported.