mail-addons/mail_recovery/data.xml

<?xml version="1.0" encoding="utf-8" ?>
<openerp>
    <data>
        <template
            id="assets_backend"
            name="message storage"
            inherit_id="web.assets_backend"
        >
            <xpath expr="." position="inside">
                <script
                    type="text/javascript"
                    src="/mail_recovery/static/src/js/mail_recovery.js"
                />
            </xpath>
        </template>
    </data>
</openerp>