wp-includes/rest-api.php:1223Gets the Application Password used for authenticating the request.
string|nullfunction rest_get_authenticated_app_password() { global $wp_rest_application_password_uuid; return $wp_rest_application_password_uuid;}Introduced in 5.7.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/rest-api.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.