评分5星,满分5星

Works find for me. You just cut and paste the word you want to know, put it in the search engine and it takes you to translate.google.com

评分3星,满分5星

Sounds like a neat add-on.

I couldn't install this add-on. Normally I install .xpi files to Thunderbird but this one is .xml. When I try to install it Thunderbird says it is an invalid package. I tried to local the author for support through the various pages (in Greek?) but I couldn't find an email address or contact link.