private function updatePermissions()
    {
        $pathNames = $this->resolver->names();
        // These should be moved to PathResolver paths eventually.
        $pathNames[] = '%web%/extensions';
        $pathNames[] = '%web%/thumbs';

        $dirMode = $this->options->getDirMode();
        foreach ($pathNames as $name) {
            $path = $this->resolver->resolve($name);
            if (!$this->filesystem->exists($path)) {
                $this->filesystem->mkdir($path);
            }
            $this->filesystem->chmod($path, $dirMode);
        }
    }