disable-embeds-wp.php

<?php
function disable_embeds_code_init() {

 // Remove the REST API endpoint.
 remove_action( 'rest_api_init', 'wp_oembed_register_route' );

 // Turn off oEmbed auto discovery.
 add_filter( 'embed_oembed_discover', '__return_false' );

 // Don't filter oEmbed results.
 remove_filter( 'oembed_dataparse', 'wp_filter_oembed_result', 10 );

 // Remove oEmbed discovery links.
 remove_action( 'wp_head', 'wp_oembed_add_discovery_links' );

 // Remove oEmbed-specific JavaScript from the front-end and back-end.
 remove_action( 'wp_head', 'wp_oembed_add_host_js' );
 add_filter( 'tiny_mce_plugins', 'disable_embeds_tiny_mce_plugin' );

 // Remove all embeds rewrite rules.
 add_filter( 'rewrite_rules_array', 'disable_embeds_rewrites' );

 // Remove filter of the oEmbed result before any HTTP requests are made.
 remove_filter( 'pre_oembed_result', 'wp_filter_pre_oembed_result', 10 );
}

add_action( 'init', 'disable_embeds_code_init', 9999 );

function disable_embeds_tiny_mce_plugin($plugins) {
    return array_diff($plugins, array('wpembed'));
}

function disable_embeds_rewrites($rules) {
    foreach($rules as $rule => $rewrite) {
        if(false !== strpos($rewrite, 'embed=true')) {
            unset($rules[$rule]);
        }
    }
    return $rules;
}
?>