I think you can. Just follow https://support.mozilla.org/en-US/kb/website-translation#w_disable-website-translations

Hello Your question, is it about a subject, popup offer to translate. If you wich to test. 1 - Go to configuration editor https://support.mozilla.org/en-US/kb/about-config-editor-firefox 2 - Enter a search term''' browser.translations.automaticallyPopup''' You can double-click on the preference to set the value to '''false''' About, languages. You can type '''about:translations''' into your address bar to see a list of available languages' models. Configure installed languages https://support.mozilla.org/en-US/kb/website-translation#w_configure-installed-languages You can test, about:translations, offline.

Traduction avec Firefox https://support.mozilla.org/fr/kb/traduction-sites-web Un test https://www.youtube.com/watch?v=HX7oWXhlohU