protected function thumbnailConfigCheck()
    {
        $thumbConfig = $this->app['config']->get('general/thumbnails');

        if ((strpos($thumbConfig['notfound_image'] . $thumbConfig['error_image'], '://') === false)) {
            $notice = json_encode([
                'severity' => 1,
                'notice'   => 'Your configuration settings for <code>thumbnails/notfound_image</code> or <code>thumbnails/error_image</code> contain a value that needs to be updated.',
                'info'     => 'Update the value with a namespace, for example: <code>bolt_assets://img/default_notfound.png</code>.',
            ]);
            $this->app['logger.flash']->configuration($notice);
        }
    }