_wp_add_additional_image_sizes

WordPress Version: 5.4

/**
 * Add additional default image sub-sizes.
 *
 * These sizes are meant to enhance the way WordPress displays images on the front-end on larger,
 * high-density devices. They make it possible to generate more suitable `srcset` and `sizes` attributes
 * when the users upload large images.
 *
 * The sizes can be changed or removed by themes and plugins but that is not recommended.
 * The size "names" reflect the image dimensions, so changing the sizes would be quite misleading.
 *
 * @since 5.3.0
 * @access private
 */
function _wp_add_additional_image_sizes()
{
    // 2x medium_large size.
    add_image_size('1536x1536', 1536, 1536);
    // 2x large size.
    add_image_size('2048x2048', 2048, 2048);
}