Unable to load the "Craft\xyz" runtime after Craft update After updating from Craft CMS 2.6.2973 to Craft CMS 2.6.2981 I get the following error message:
"Unable to load the "Craft\xyz" runtime after Craft update"


"Craft\xyz" is a Twig extension
Fails in [install folder]\craft\app\vendor\twig\twig\lib\Twig\Environment.php line 900 (Twig_Environment::getRuntime())
Twig_Environment::runtimes is an empty array


Anyone else experienced this problem, and know what is causing it?

Thanks in advance!
Fixed by changing:

class xyz extends \Twig_Extension
{
    //...
    public function getFunctions()
    {
        return array(
            new \Twig_SimpleFunction('kex_cache_breaker', array(__CLASS__, 'cacheBreaker'))
        );
    }
    //...
}


To:

class xyz extends \Twig_Extension
{
    //...
    public function getFunctions()
    {
        return array(
            new \Twig_SimpleFunction('kex_cache_breaker', array($this, 'cacheBreaker'))
        );
    }
    //...
}