_wp_add_additional_image_sizes() │ WP 5.3.0

Adds 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.

Internal function — this function is designed to be used by the kernel itself. It is not recommended to use this function in your code.

No Hooks.

Return

null. Nothing (null).

Usage

_wp_add_additional_image_sizes();

Changelog

Since 5.3.0 Introduced.

_wp_add_additional_image_sizes() code WP 6.5.2

wp-includes/media.php 
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 );
}