[horde] How to Configure Turba to Display and Store up to 3 Email Addresses

[INFO - Digital Style Informatica]

    How to Configure Turba to Display and Store up to 3 Email Addresses

Is it still the right solution?

https://wiki.horde.org/TurbaExtraFields

I've found in my configuration on Horde 5.2.22 this:

$attributes['emails'] = array(
     'label' => _("Emails"),
     'type' => 'email',
     'required' => false,
     'params' => array('allow_multi' => true, 'strip_domain' => false, 
'link_compose' => true, 'link_name' => null, 'delimiters' => ',', 'size' 
=> null)
);

There is another way to configure multiple email address and than sync 
on thunderbird using CardBook extension and on Android using CardDav app?