Looking at `core/maintenance/archives/patch-watchlist-null.sql`, the watchlist table `wl_notificationtimestamp` attribute was introduced support for NULL by default and so doing, adding an article to watchlist table doesn't add it's current timestamp (tested locally) but adds `NULL` instead.
Sometimes, users watchlist entries can grow as large as >700 pages/articles (use-case) and knowing the latest article added to watchlist is a bit difficult (taking into consideration the user can't remember the name of this particular article) so I was experimenting on building an extension (say WatchListFilter) to filter watchlist based on various parameters but by default, based on their timestamps added.
So, filtering by timestamp (default) will make the latest added article appear first (DESC order by time) on the [[ https://en.wikipedia.org/wiki/Special:EditWatchlist | Special:EditWatchlist ]] page which is useful but this means the `watchlist` table needs to be altered a little bit I guess?
I believe MW has some way of dealing with TS, maybe this: https://www.mediawiki.org/wiki/Manual:Timestamp and if so, should the table be altered to avoid NULL by default or should it be as-is and just some logic added to include saving these TS when article is added to watchlist by user instead of NULL?
Would like to have input on this please. Thanks!
Other topics as per how the filter will look on the Special:EditWatchlist special page based on the OOUI-fication that has happened and others can be address on other tickets, maybe sub-tasks of this one I guess :) Also, not sure of what tags to add to this ticket so added a few.