Undefined array key in tnp_composer_block_posts_get_media

Function tnp_composer_block_posts_get_media() is called with a $size parameter from e.g. emails/blocks/posts/layout-two.php which there contains this:

$size = array(600, 400, $image_crop);

If no $post_thumbnail_id is available the function tries $default_image_url and gets width/height via array keys from $size:

} elseif ($default_image_url) {
    Newsletter::instance()->logger->error('Thumbnail id not found');
    $media = new TNP_Media();
    $media->url = $default_image_url;
    $media->width = $size['width'];
    $media->height = $size['height'];

These array keys do not exist in above described case and cause these warnings:

[10-May-2025 09:40:51 UTC] PHP Warning: Undefined array key "width" in …/wp-content/plugins/newsletter/includes/helper.php on line 461
[10-May-2025 09:40:51 UTC] PHP Warning: Undefined array key "height" in ../wp-content/plugins/newsletter/includes/helper.php on line 462

Newsletter 8.8.2