https://w3c.github.io/epub-specs/epub33/core/#sec-container-filenames

All File Names within the same directory MUST be unique following case normalization as described in section 3.13 of [Unicode].

This sentence does not seem to be very clear. Would you please clarify what algorithm of "case normalization" is used here? Is it Unicode full or simple casefolding?

Please refer to Case Mapping and Case Folding and Additional Considerations for Case Folding in charmod-norm.