wp-admin/includes/class-wp-ajax-upgrader-skin.php:77Retrieves the list of errors.
WP_Error public function get_errors() { return $this->errors; }Introduced in 4.6.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-admin/includes/class-wp-ajax-upgrader-skin.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.