dynamic-caption-featured-image-elementor.php

<?php
add_action('elementor/widget/render_content', function( $content, $widget ) {
  
    if ('theme-post-featured-image' === $widget->get_name()) {
        $settings = $widget->get_settings();

           $caption=get_the_post_thumbnail_caption(get_the_ID());
            $content .= '<figcaption class="widget-image-caption wp-caption-text">' . $caption . '</figcaption>';
      
    }

    return $content;
}, 10, 2);
?>