When the formatting marks (and hidden text) are toggled off (not showing) in
a document, how can I determine whether or not the selection contains hidden
text? Or whether the paragraph before or after the selection is hidden?

I'm trying to put a frame around the selected paragraphs, anchored in the
following paragraph. But if a hidden paragraph precedes the selection, it
somehow always gets included in the framed material.

Similarly, if a hidden paragraphs follows the selection, the frame gets
anchored in the hidden paragraph. (I'm sure that will be a problem.)

I just need to detect hidden paragraphs and warn the user. But how?

Bear