wp-includes/html-api/class-wp-html-processor.php:5139Indicates the namespace of the current token, or "html" if there is none.
string public function get_namespace(): string { if ( ! isset( $this->current_element ) ) { return parent::get_namespace(); } return $this->current_element->token->namespace; }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-processor.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.