>And Web Serial reached mainline Firefox last week.

That's good news. I wish FF wasn't so conservative... they're missing a lot of cool APIs. Sometimes I wonder who they think their audience is. I suppose they would know better than I would.

I think they see privacy as one of their primary valueadds, and are concerned about the privacy implications with exposing a (PAN) network to the internet that probably wasn't designed to be exposed to such an adversarial environment.