{% load i18n creme_widgets %}
{% if button.permission_error %}
<span class="menu_button menu-button-icon forbidden" title="{{button.permission_error}}">
    {% widget_icon name='phone' size='instance-button' label=_('Phone call') %}
    {{button.verbose_name}}
</span>
{% else %}
<a class="menu_button menu-button-icon" title="{{button.description}}" data-action="update"
   href="{% url 'activities__create_unsuccessful_phone_call' object.id %}">
    {% widget_icon name='phone' size='instance-button' label=_('Phone call') %}
    {{button.verbose_name}}
</a>
{% endif %}