Sometimes it works but not always. Must be a bug somewhere.

When I attempted to use Google Translator for Firefox by nobzol, nothing at all happened. There were no instructions or hints at all on how to use it.

It is a good plugin. But I think the following plugin has better performance and easier access for translation and is much like Google Translator itself. Of course, this is a personal opinion. I communicated more with this
Plugin Name: Page Translator by Fire360Boy

Não funciona para a página inteira

i preferred the previous version, when the text was translate on the page and was replacing the actual text with the translation ! now you are just as lame as all the others plugins...

Он даже эту страницу перевести не может

Non funziona più....cosa devo fare????

Open a small window in page but apparently not able to translate anything in any language

Firefox 73.0.1 (64 bity). Dodatek nie działa, po wciśnięciu "T" nie rozpoznaje języka i czasem zawiesza przeglądarkę. Nie działa również tłumaczenie zaznaczonego tekstu.