Systems without the Arial font will default to other fonts, but the replacement might or might not be an appropriate substitute. It seems to work fine under CentOS and MacOS but not under Ubuntu.
Steps to reproduce:
Choose the preset/template with parents and grandparents
Click on right grandmother (rightmost top node) and enter a 35+ char first name and a 35+ last name
Export pedigree to png
If rendered correctly, it means the system the PhenoTips application is running on has a suitable font.