wp-includes/html-api/class-wp-html-open-elements.php:498Returns whether a P is in BUTTON scope.
bool public function has_p_in_button_scope(): bool { return $this->has_p_in_button_scope; }Introduced in 6.4.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/html-api/class-wp-html-open-elements.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.