wp-includes/class-wp-customize-widgets.php:2122int protected function count_captured_options() { return count( $this->_captured_options ); }Introduced in 3.9.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/class-wp-customize-widgets.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.