Definition of browser field in my panel.js, but it returns only one argument (data about selected image), but there is no info in which Media Source was file selected.

MODX Combo browser - media source of selected file

{
    name: 'annex',
    fieldLabel: _('workshops.annex'),
    xtype: 'modx-combo-browser',
    id: this.ident +'-annex',
    maxLength: 250,
    hideFiles: true,
    listeners: {
        'select': {
            fn: function(data) {
                console.log(arguments);
            },
            scope: this
        }
    }
}

Only what I get in console is result:

Object
cls: "icon-access"
dateString: "12/03/2012 9:18 am"
disabled: false
ext: "access"
fullRelativeUrl: "ht.access"
image: "/www/manager/templates/default/images/restyle/nopreview.jpg"
image_height: 60
image_width: 80
lastmod: Mon Dec 03 2012 09:18:10 GMT+0100 (Střední Evropa (běžný čas))
menu: Array[1]
name: "ht.access"
pathname: "D:/www/modx.revolution.test/www/\ht.access"
relativeUrl: "ht.access"
shortName: "ht.access"
size: 3519
sizeString: "3.4 KB"
thumb: "/www/manager/templates/default/images/restyle/nopreview.jpg"
thumb_height: 60
thumb_width: 80
url: "ht.access"
__proto__: Object