I recommend "S3.Translator" as a translation extension


#1

Continuing the discussion from Google translate extension:
Based on this thread
How is the extension “S3.Translator” using the public API of “Google Translate”?


#2

That extension has been proven as an add-on to Firefox.
https://addons.mozilla.org/ja/firefox/addon/s3google-translator/
It is also open to the ChromeWebStore.


Official site is http://www.s3blog.org/s3translator.html