Which Dashboard takes precedence when a user belongs to multiple User Groups?

Interesting question relating to permissions... if a single user is a member of multiple user groups, the user's permissions will the most permissive defined between the groups (e.g. if a user is a member of 2 user groups A and B, and User Group A can't do X, but User Group B can do X, then the user will be able to do X). But since each User Group can define its own custom dashboard, say Dashboard A and Dashboard B, how does MODX determine which dashboard is displayed when that user logs in?

The dashboard for the user's "Primary Group". The Primary Group is the user group with rank 0, or the top group when editing a User and seeing their list of groups.

Thanks!