wp-includes/SimplePie/src/Source.php:335Added for parity between the parent-level and the item/entry-level.
string|null public function get_permalink() { return $this->get_link(0); }One change between 6.7.7 and 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
none to string|null.verified against sourcesrc/wp-includes/SimplePie/src/Source.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.