rhamzeh

We already have it as a non-XUL extension, so I don't see what your issue with it is? Just that it is not built it?

https://addons.mozilla.org/firefox/addon/firefox-translations/

You can already install the extension and use it today. Also AFAIK the XUL extension was not local only translation

I believe it was this year that they made some great improvements in performance, so you might get a different experience if you try it again.