WordPress: Remove unwonted image sizes, like medium_large, 1536x1536, 2048x2048

functions.php

<?php

/*
 * WordPress: Remove unwonted image sizes.
 * In this code I remove the three sizes medium_large, 1536x1536, 2048x2048
 * See full article: 
 */

add_filter('intermediate_image_sizes', function($sizes) {
  return array_diff($sizes, ['medium_large']);  // Medium Large (768 x 0)
});

add_action( 'init', 'j0e_remove_large_image_sizes' );
function j0e_remove_large_image_sizes() {
  remove_image_size( '1536x1536' );             // 2 x Medium Large (1536 x 1536)
  remove_image_size( '2048x2048' );             // 2 x Large (2048 x 2048)
}