This content was released on Oct 3 2019. The official support period is 6-months from this date.
Switch from Force Dark to instead use an AppCompat DayNight theme, so that the themes will work on earlier versions of Android, and then a MaterialComponents DayNight theme.
This is a companion discussion topic for the original entry at https://www.kodeco.com/5697228-supporting-dark-theme/lessons/2