xmpp.chapril.org-conversejs/src/templates/add_contact_form.html

<li>
    <form class="pure-form add-xmpp-contact">
        <input type="text"
            name="identifier"
            class="username"
            placeholder="{{label_contact_username}}"/>
        <button class="pure-button button-primary" type="submit">{{label_add}}</button>
    </form>
</li>