Since 2018 ruwiki has an "engineer" usergroup for technical admins, its users got the same "editprotected" permissions as admins. When "interface admin" group was created, there was created several new permissions like "editsitejs" and "editusercss", most of them was given to IA only, "editsitejson" was given to admins and engineers, but "edituserjson" was given only to admins, but not engineers. It's look like an error in permissions' management and we request to add "edituserjson" permission to engineers too.
Local discussion: https://ru.wikipedia.org/wiki/Википедия:Форум/Общий#edituserjson_для_инженеров