muk_web/muk_web_export_attachment/static/src/xml/sidebar_preview.xml

<?xml version="1.0" encoding="UTF-8"?>

<!--     
	Copyright (C) 2017 MuK IT GmbH
	
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as
    published by the Free Software Foundation, either version 3 of the
    License, or (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>. 
-->

<templates>
	<t t-extend="Sidebar">
		<t t-jquery="a:has(.o_sidebar_delete_attachment)" t-operation="before">
			<span t-if="section.name == 'files' and !item.callback and item.url"
				t-attf-class="fa fa-sign-out o_sidebar_export_attachment {{ item.exportable }}"
				t-att-data-id="item.id" t-att-data-url="item.url" t-att-data-name="item.name"
				title="Export this attachment" />
		</t>
	</t>
</templates>