Annotations cannot be created for non-"text" data, such as chapter and verse numbers and paragraph breaks

[tombogle]

The UsxFragmenter class currently does not create fragments for paragraph breaks, chapter numbers, and verse numbers, so there is no way for a plugin to create an annotation that covers the HTML nodes that get generated for these.
(Tim thinks that it might be a simple matter of changing AppendStartUsfm to add fragments for these things.)
Note that in an ideal world, it would be nice for a plugin to be able to indicate that an annotation should cover both the \c and its data or the \v and its data rather than having to create separate annotations for these.