wp-includes/widgets.php:341Removes a sidebar from the list.
$sidebar_idstring|intfunction unregister_sidebar( $sidebar_id ) { global $wp_registered_sidebars; unset( $wp_registered_sidebars[ $sidebar_id ] );}Introduced in 2.2.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/widgets.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.