Library button is not visible in DPS apps on iPhone with iOS 11

Digital Publishing Suite
iOS 11
iPhone

Cause

A change in how iOS handles fonts caused unexpected shifting of user interface elements.

Resolution

Rebuild the app with release 32.6.8. This release, available in the DPS App Builder as of September 28, 2017, resolves the iOS 11 problem with iPhone viewers where the Library back button does not appear due to long publication names.