wp-includes/class-wp-customize-setting.php:721Deprecated method.
protected function _update_theme_mod() { _deprecated_function( __METHOD__, '4.4.0', __CLASS__ . '::update()' ); }Introduced in 3.4.0. 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-setting.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.