There are some missing properties from the user preferences tables. Reimport them from the backups.
|mediawiki/extensions/WikimediaMaintenance : master||[WIP] Add script to select old user_properties entries from backup|
|Open||None||T38316 Set "Add pages I edit to my watchlist" and "Add pages I create to my watchlist" to true by default on Wikimedia wikis (only for new users)|
|Open||None||T54777 user_properties table bloat|
|Resolved||demon||T114208 User skin preference for MonoBook changed to default (Vector) on small and medium wikis (about 95% of wikis)|
|Duplicate||demon||T114899 Recover missing values from user_properties tables|
Due to the time that has passed since the values were lost, we are only going to reimport the missing values for now, to avoid annoying users again that may have already changed their preferences.
We can recover preferences on an individual bases, though, if they have not been changed since the commit.