Change 698784 had a related patch set uploaded (by Esanders; author: Esanders):

[mediawiki/core@master] Enable watchlist expiry by default

https://gerrit.wikimedia.org/r/698784

Watchlist expiry is enabled everywhere for WMF, but most third party wikis will probably have little use for it. The watchlist system is already kind of confusing for new users, and with the expiry feature enabled you get a form that shows up that almost looks like you have to do something, adding even more confusion. Perhaps we can improve that experience to be more intuitive, but in my humble opinion this feature should not be default-on because it just adds UI cruft for the vast majority of wikis.

I agree with MusikAnimal: for the majority of MediaWiki installations, watchlist expiry is likely to not be required. Of course it can always be turned of for wikis that don't want it, but I think it should stay as default-off.

Change 698784 abandoned by Esanders:

[mediawiki/core@master] Enable watchlist expiry by default

Reason:

https://gerrit.wikimedia.org/r/698784

I think this is a mistake. Carrying the product debt of yet another feature flag is not something we should do based on supposition of the confusion caused by our own products.

In T284563#7158225, @Jdforrester-WMF wrote:

I think this is a mistake. Carrying the product debt of yet another feature flag is not something we should do based on supposition of the confusion caused by our own products.

This task was about enabling the feature flag by default, not removing it. But either way I maintain watchlist expiry as a feature – no matter how intuitive – is not very useful except for large-ish wikis where users are watching a lot of pages.