TOC as Widget: Filters ez_toc_before + ez_toc_after not working.

Hi. The filters ez_toc_before + ez_toc_after are working fine, if the TOC is included automatically into the main article.

Problem: If I insert the TOC as a Widget in the sidebar, these filters unfortunately aren’t applied.

<?php
add_filter('ez_toc_before', static function () {
    echo '<p>Intro text for TOC</p>';
});
add_filter('ez_toc_after', static function () {
    echo '<p>Outro text</p>';
});