public function getFallbackLanguages()
    {
        if (empty($this->fallback_languages)) {
            if ($this->enabled()) {
                $fallback_languages = $this->languages;

                if ($this->active) {
                    $active_extension = $this->active;
                    $key = \array_search($active_extension, $fallback_languages, true);
                    unset($fallback_languages[$key]);
                    array_unshift($fallback_languages, $active_extension);
                }
                $this->fallback_languages = $fallback_languages;
            }
            // always add english in case a translation doesn't exist
            $this->fallback_languages[] = 'en';
        }

        return $this->fallback_languages;
    }