wp-includes/category.php:276Sanitizes data in single category key field.
$fieldstring$valuemixed$cat_idint$contextstringmixedfunction sanitize_category_field( $field, $value, $cat_id, $context ) { return sanitize_term_field( $field, $value, $cat_id, 'category', $context );}Introduced in 2.3.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/category.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.