How to add your own column to the users section of isp manager?

Question

ISPmanager

Advise, colleagues, where to look? Now I did the following:
/usr/local/mgr5/etc/sql/
created the users.addon folder
in it the comment file (empty, without extension)
/usr/local/mgr5/etc/xml/
created the ispmgr_mod_comments.xml file

<?xml version="1.0" encoding="UTF-8"?>
<mgrdata>
    <metadata name="user.edit">
        <form>
            <page name="main">
                <field name="comment">
                    <input type="text" name="comment"/>
                </field>
            </page>
        </form>
    </metadata>
    <metadata name="user" type="list">
        <coldata>
            <col name="comment" after="fullname" type="data" />
        </coldata>
    </metadata>
    <lang name="ru">
        <messages name="user.edit">
            <msg name="comment" sqlname="comment">Комментарий</msg>
        </messages>
    </lang>
</mgrdata>

As a result:
I see the column, but I don’t see the values, although everything is in the form (I can add and save)