Value shows as 'Array' for second participant

Adding an array of checkboxes to a profile (in this case Supporter profile on the demo site) shows the information entered for the first registrant on the thank you screen but just 'array' for the second. Note field test array below

Supporter Profile
First Name Christian
Last Name Pearce
test: pd test green
membership: Chapter - select -
membership: test array [ ]Education [x]Environment [ ]Social Justice
Participant Information - Participant 2
Supporter Profile
First Name test
Last Name test
membership: test array Array

I registered two users in this event and left the test array field blank for the second participant