in src/main/java/org/apache/sling/jcr/repoinit/impl/UserVisitor.java [166:171]
private void checkUserType(@NotNull String id, @Nullable User user, boolean expectedSystemUser) {
if (user != null && user.isSystemUser() != expectedSystemUser) {
String msg = (expectedSystemUser) ? "Existing user %s is not a service user." : "Existing user %s is a service user.";
report(String.format(msg, id));
}
}