How to Limit or Disable WordPress Revisions (ok)

https://www.inmotionhosting.com/support/edu/wordpress/limit-or-disable-wordpress-revisions/

C:\xampp\htdocs\wordpress1\wp-includes\revision.php

$num = apply_filters( "wp_{$post->post_type}_revisions_to_keep", $num, $post );

C:\xampp\htdocs\wordpress1\wp-content\themes\twentytwentyone\functions.php

add_filter('wp_post_revisions_to_keep','callback_wp_revisions_to_keep',10,2);
function callback_wp_revisions_to_keep($num, $post) {
   return 2;
}