public function getNamespaceDefinitions(): string
    {
        $script = 'var Frontend = {};';
        $script .= 'var App = { Controllers: {}, Components: {}, Lib: {} };';
        $tpl = 'App.Controllers.%s = {};';
        foreach ($this->_pluginJsNamespaces as $pluginName) {
            $script .= sprintf($tpl, $pluginName);
        }

        return $this->Html->scriptBlock($script);
    }