Useful WordPress functions

Removing default image sizes in WordPress.

add_filter('intermediate_image_sizes_advanced', 'remove_default_image_sizes');
function remove_default_image_sizes($sizes) {
    unset($sizes['medium_large']);
    unset($sizes['1536x1536']);
    unset($sizes['2048x2048']);
    return $sizes;
}
update_option('medium_large_size_w', 0);
update_option('medium_large_size_h', 0);

add_filter('big_image_size_threshold', '__return_false');