Firefox

Sure, there are possibilities, I'm just very sceptical of the browser itself being the producer of the content I consume. Sometimes translation is necessary of course, so it's not a rule set in stone.

I agree with you accessibility could be one field where it could be very useful. If this is the priority, I think Mozilla should say they prioritize accessibility, not that they prioritize AI. Machine learning can be a useful tool towards certain ends, but it con never be an end in its own right.