Safari Prevents Duo From Saving Authentication For 12 Hours

When authenticating to a UW site with Duo using Safari the "remember me for 12 hours" session check box is blocked by a warning message "You need to enable cookies in order to remember this device".

Solution, open Safari preferences, go to Privacy and un-check at Website tracking "Prevent cross-site tracking" to allow the Duo session for 12 hours.
Duo Box