for my part, it would probably mean that GitFileTree isn't loaded. Do you have a package named MonticelloFileTree-Git? I load it with: �������� Gofer new ��� ��� ��� ��� url: 'http://smalltalkhub.com/mc/Pharo/MetaRepoForPharo30/main'; ��� ��� ��� ��� configurationOf: 'GitFileTree'; ��� ��� ��� ��� loadDevelopment