It should be noted that this isn't quite the same AI integration that the likes of Google/Microsoft are working on.
It's trained using the data you authorise it to have, is run entirely locally when your browser is otherwise doing nothing, and doesn't send information back to Mozilla.
Personally my main gripes with AI are unethical sourcing of training data, and data collection. It seems like these won't be problematic in this case.
If AI integration is to happen (and we need to wait and see what the wider market outside of the Lemmy bubble wants), then this to me seems to be the best way to do it.
Right now they're using 'AI' for detecting fake reviews on sites, and to help power their offline translation.
As for the 60 layoffs, that's a shame and I hope these people find swift employment. They don't appear to be people working on Firefox, though.