[site-reviews] replace avatar with page featured image

// This will only work for Site Reviews v5

/**
 * Add a new WordPress image size for Site Reviews avatars
 * Paste this in your active theme's functions.php file.
 * This will only work for Site Reviews v5
 * @return void
 */
add_action('after_setup_theme', function () {
    $fallback = 40; // fallback width/height in pixels
    $size = apply_filters('glsr_get_option', $fallback, 'reviews.avatars_size', $fallback);
    add_image_size('site-reviews-avatar', $size, $size, true);
});

/**
 * Replaces the review avatar with the featured image thumbnail of the assigned page
 * Paste this in your active theme's functions.php file.
 * @param string $value
 * @param \GeminiLabs\SiteReviews\Modules\Html\Tags\ReviewAvatarTag $tag
 * @return string
 */
add_filter('site-reviews/review/value/avatar', function ($value, $tag) {
    $firstAssignedPostId = array_shift($tag->review->assigned_posts);
    if (empty($firstAssignedPostId)) {
        return $value;
    }
    $thumbnail = get_the_post_thumbnail($firstAssignedPostId, 'site-reviews-avatar');
    if (empty($thumbnail)) {
        return $value;
    }
    return $thumbnail;
}, 10, 2);