Choice of full posts or excerpts not available

Customer > Content Options is not available in the downloadable theme the way it is supposed to be in the WordPress.com version:

Baskerville 2 supports all Content Options, including the ability to display your choice of full post content or excerpts on the blog and archives.

As a result, there is no way to display excerpts on the home page (when recent posts is chosen).

This option was available until a recent update. Now broken.