My work involves renaming audio files with specific placement of dashes and underscores, and depends on standard Mac text navigation using "Option" and the right/left arrows. The convention is navigation SKIPS underscores, but STOPS on dashes.
ProTools 12.8 STOPS on underscores AND dashes.... ProTools 12.5 skips over underscores as expected.
Text functions on other Mac Sierra software (mail, text editors) follow the "Skip Underscore" convention, only ProTools stops on underscores.
Not sure if this change is deliberate or an oversight, but hope the conventional text navigation is restored in the new versions of ProTools.