Canon has released Digital Photo Professional 3.8.2 Updater for Mac OS X (only). Select Mac OS X on the landing page.
Changes for Digital Photo Professional 3.8.2 Updater for Mac OS X:
Fixes a malfunction wherein the trimming ratio is entered abnormally when it is set to Custom using the trimming/angle adjustment tool, and also when the trimming area is copied to other images.
(thanks neuroanatomist)