Non-admin Confluence users are unable to see users within the Mugshot Gallery macro

Description

Confluence users are unable to view users displayed in the mugshot gallery macro unless they are a member of the confluence-administrators group or Anonymous users are granted access to 'View User Profiles' 

Steps to reproduce

• Add the Mugshot Gallery macro to a page
• Ensure that the Global permission anonymous 'View User Profiles' option is not selected
• View the page containing the macro as a user that is not included in the confluence-administrators group

Expected outcome

The user will see a list of confluence users that are included in the group specified 

Actual outcome

The user is presented with the following error: