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

<div class="modal" id="room-registration-modal" tabindex="-1" role="dialog" aria-labelledby="room-registration-modal-label" aria-hidden="true">
    <div class="modal-dialog" role="document">
        <div class="modal-content">
            <div class="modal-header">
                <h5 class="modal-title" id="room-registration-modal-label">{{{o.display_name}}}</h5>
                <button type="button" class="close" data-dismiss="modal" aria-label="{{{o.label_close}}}"><span aria-hidden="true">×</span></button>
            </div>
            <div class="modal-body">
                <form class="converse-form">
                    {[ if (o.feedback.get('error')) { ]} <div class="alert alert-danger" role="alert">{{{o.feedback.get('error')}}}</div> {[ } ]}
                    {[ if (!o.feedback.get('error')) { ]} <span class="spinner fa fa-spinner"></span> {[ } ]}
                </form>
            </div>
            <div class="modal-footer">
                <button type="button" class="btn btn-secondary" data-dismiss="modal">{{{o.__('Close')}}}</button>
            </div>
        </div>
    </div>
</div>