gistfile1.txt

<?php
/**
 * Plugin Name: Disable Thumbnails Embeds
 * Description: Don't like the thumbnails embed?
 * Version:     1.0
 * Author:      Julio Potier
 * Author URI:  https://wp-rocket.me    
 * License:     GPLv2+
 *
 */

add_filter( 'embed_thumbnail_image_shape', '__return_false' );