{% with _active = (active is not defined or active or active is none) %}
    <td class="{{ model.FLAG_ACTIVE }}">
        {# 
            <input class="{{ model.FLAG_ACTIVE }}" type="checkbox" {% if active %}checked{% endif %} {{ model.ATTR_VALUE_CURRENT }}="{{ active | lower }}" {{ model.ATTR_VALUE_PREVIOUS }}="{{ active | lower }}">
        #}
        <button type="button" class="{{ model.FLAG_ACTIVE }} {% if active %}{{ model.FLAG_DELETE }}{% endif %}" 
            {{ model.ATTR_VALUE_CURRENT }}="{{ active | lower }}" 
            {{ model.ATTR_VALUE_PREVIOUS }}="{{ active | lower }}"
        >{% if active %}x{% else %}+{% endif %}</button>
    </td>
{% endwith %}