Firefox

I'm in the middle of learning a new language and trying to expose myself to the language. And this add-on (https://addons.mozilla.org/en-GB/firefox/addon/youtube-dual-subtitles/), I found this very helpful. But because it had access to YouTube, it will automatically download the subtitle (or the auto-generated one) and translate it. What worries me is where and how it got translated and what it's doing with my activity. Also, sometimes it just doesn't work at all.

So are there any add-ons similar to this? That you can customize it how it translates stuff, e.g. via local LLM or via translation service of your choosing. Other suggestions to achieve the same goal are welcomed!

~~I hope Firefox has more capabilities like Auto Translate Live Caption~~