wp-includes/class-wp-customize-panel.php:215Default callback used when invoking WP_Customize_Panel::active().
bool public function active_callback() { return true; }Introduced in 4.1.0. 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-panel.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.