[RCD] Add button to Address Book

Hi all, I am migrating address book from horde to roundcube. I have a script called migrate.php to do the job. I would like to make a button (i.e. next to the 'export contacts in vCard format) that will execute the migrate.php. I have the button up, but it is disable. I add

<roundcube:button command="importhorde" type="link" class="buttonPas importhorde" classAct="button importhorde" classSel="button importhorde" title="importhorde" content=" " />

to skins/templates/addressbook.html

1. How can I make the button enable to click ?

2. How can I make the script running when the button is clicked ?

3. How can I change the icon/images of the button ? It uses the same image

as the 'Add new contact'

Thank you.

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