wp-includes/SimplePie/src/Item.php:161Get the base URL value.
$elementarrayoptional[]string public function get_base($element = []) { if (!empty($element['xml_base_explicit']) && isset($element['xml_base'])) { return $element['xml_base']; } $link = $this->get_permalink(); if ($link != null) { return $link; } return $this->feed->get_base($element); }Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/SimplePie/src/Item.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.