hehe/user/plugins/admin/themes/grav/templates/partials/page-legend.html.twig

{% set legend = {'VISIBLE':'', 'NON_ROUTABLE':'not-routable', 'NON_VISIBLE':'not-visible', 'MODULAR':'modular'} %}
<div id="pages-legend">
    <strong>{{ 'PLUGIN_ADMIN.LEGEND'|tu }}:</strong>
    <ul>
        {% for key, class in legend %}
        <li><i class="page-icon fa fa-fw fa-circle-o {{ class }}"></i> {{ ('PLUGIN_ADMIN.'~key)|tu }}</li>
        {% endfor %}
    </ul>
</div>