Mozilla developers have released an extension for the Firefox browser called Firefox Translations that provides offline text translation. The system allegedly uses computer resources for translation rather than sending information to a cloud data center.
After the first run, the translator will download some files, but you can use it without an Internet connection.
Currently only 13 languages are supported. The list includes English, Spanish, Bulgarian, Czech, Estonian, German, Icelandic, Italian, Norwegian and Nynorsk, Persian, Portuguese and Russian. For comparison, Google Translate supports 133 languages, Yandex Translator – 98. Also note that the translation into Russian is still in beta, so there may be errors.
The extension was developed by Mozilla in collaboration with the European Union funded Bergamot project. The extension itself can be installed from the directory (only for Firefox, Chrome and others). Firefox ranked fourth on the list with 179 million users as of May this year.