1) start Syncope in embedded mode and delete all roles or deploy syncope project with empty (default) content.xml
2) log into console and create an user.
3) go under roles tab in user modal page and click on empty role (the only displayed), a membership modal window is shown.
4) click on save button and you'll notice a NullPointerException.
This is due to the fact that, if there are no roles, in edit user modal page is possible to create membership between root (fake) role (the one with id 0) and user and this is incorrect because root role is not useful for creating a membership.