in teamcity-invitations-plugin-server/src/main/java/org/jetbrains/teamcity/invitations/JoinProjectInvitationType.java [97:102]
private List<SUserGroup> getAvailableGroups(@NotNull AuthorityHolder user, @NotNull SProject project) {
return core.getAvailableGroups().stream()
.filter(group -> !group.getRolesWithScope(RoleScope.projectScope(project.getProjectId())).isEmpty())
.filter(group -> ServerAuthUtil.canAddToRemoveFromGroup(user, group))
.collect(toList());
}