(It may be best to make an entirely new group with new URL parameter, since there are some significant behavioral changes and this will make adapting the URL easier.)
The 'Watchlisted pages' filter group will be useful on the Watchlist, but needs to be adapted for this new setting.
=Required changes
- The group moves to the top of the filter list (above the ORES filters).
- The title of the group becomes "Watchlist activity" (instead of "Watchlisted pages")
- The "On Watchlist" filter is eliminated (because everything here is on Watchlist)
- The "Not on Watchlist" filter is eliminated (obviously).
- A new filter is added, "Seen changes". This filter identifies all changes to pages the user has not visited since the changes occurred.
- The "New Watchlist changes" filter is renamed "Unseen changes"
- Together, the Seen and Unseen filters constitute total coverage for this page.
- New filter descriptions and other language are shown below.
=New UI language
===Watchlist activity
**Unseen changes**
Changes to pages you haven't visited since the changes occurred.
**Seen changes**
Changes to pages you have visited since the changes occurred.