{% load wagtailadmin_tags %}

{% auto_update_preview as auto_update %}
<button class="button action-preview {% if icon %}icon icon-view{% endif %}"
    data-action="{% url 'wagtailadmin_pages:preview_on_edit' page.id %}{% if mode %}?mode={{ mode|urlencode }}{% endif %}"
    data-auto-update="{{ auto_update|yesno:'true,false' }}">{{ label }}</button>