wp-includes/compat.php:657Polyfill for array_first() function added in PHP 8.5.
$arrayarraymixed|null function array_first( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound if ( empty( $array ) ) { return null; } foreach ( $array as $value ) { return $value; } }Introduced in 6.9.0. Unchanged from 6.9.7 through 7.1.0.
Signature, return type and hooks compared across 3 parsed releases.
src/wp-includes/compat.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.