It is unclear which features should be configurable in application settings, and which should be set or overridden for each document

I think it would be valuable to provide guidance on what users' needs are with respect to the configurability of the features described in the Requirements. For example, which features should be controlled by an application's general settings? Which should be set or overridden for individual documents? Should per-document settings be saved?

I don't think extensive guidance is needed. Rather, a short section on configurability, or brief notes within each section describing a relevant feature should suffice.

The issue points to the Requirements document; review its feature sections and identify where application-wide versus per-document configurability needs guidance. Done means adding a short configurability section or concise notes in relevant sections, including whether per-document settings are saved.

Written by the indexing model from the issue text.