I would like the diff link in the watchlist show changes since my last visit, not just the diff of the last edit made to the page. Or maybe there should be two diff links. I can go view that diff in three clicks now, and it would be very convenient to be able to do it in just one. I guess this should not be very hard.
Topic on Talk:Watchlist wishlist/Archive 1
Are you using the extendedwatchlist preference ("Expand watchlist to show all changes, not just the most recent")?
Whoa, never noticed that. Just tried it, and it does not seem to be what I want. It looks like a diff of changes made within the span of the whole day, not just since my last visit.