Because workspaces have a more sensible membership relationship (membership to the workspace group), the new User Directory can no longer display users based on the default membership relationship (Pages with XWikiUsers objects).
To accomodate this, the workspace-template-features package will provide an override UserDirectoryLivetableResults page that will properly build the query to be used by the workspace's User Directory.
The idea is that this query will display all global direct and indirect users that are members of the workspace's group. Indirect users means all global users that are members of a global group that is also a subgroup of the workspace's group. The subgroups are explored recursively, down the subgroup levels and only global groups are considered.