wp-includes/media.php:2068Prints a CSS rule to fix potential visual issues with images using sizes=auto.
One hook fires while wp_print_auto_sizes_contain_css_fix() runs, in this order:
Filters whether auto-sizes for lazy loaded images is enabled.
function wp_print_auto_sizes_contain_css_fix() { /** This filter is documented in wp-includes/media.php */ $add_auto_sizes = apply_filters( 'wp_img_tag_add_auto_sizes', true ); if ( ! $add_auto_sizes ) { return; } ?> <style>img:is([sizes="auto" i], [sizes^="auto," i]) { contain-intrinsic-size: 3000px 1500px }</style> <?php}Introduced in 6.7.1. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/media.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.