That’d certainly be a good feature, but it feels to me like it’s a fairly niche need. And as per that post, it’s also a big technical effort. I can see why there isn’t anything in the way of development updates.
That is me being a bit of an apologist for Firefox though. If you consider Firefox unusable because of that, then that’s a pretty valid frustration.
Still, I’d encourage you to try and find a way to make it work for you because Chrome is evil.