Format used to display content information and relative modify timestamp.

%1$s – xVideos, xPhotos or format_photosAndVideos string
%2$s – one of timestamp_* strings. today_shortened is used as a resource for today.

Example: "74 photos, modified just now", "5 videos, modified at 7:40", "1 photo, 44 videos, modified yesterday at 12:30"