A very similar feature comes out of the box with Vivaldi[0], which I have been trying out recently. Whilst I'm particularly enjoying all the configurability so far, it's too early for me to recommend it.
I really like Vivaldi, but at this point it’s not performant enough for me to use it on all devices. On a new MacBook Air, the UI visibly lags at times, and when doing video calls it’s unusably slow. I’m looking forward to future versions where this is hopefully improved, although on a stronger machine it’s probably fine.
What is the appeal of Vivaldi browser? I know it is started by Opera's CEO but it is closed-source (only the chromium part is open-source). The only feature I like is tab split view.
Even stack tabs by host is not unique with this extension is it? :)
It's made for power users as I said, for example you can change the right click menu on the tab bar and have only things you care about in there instead of 1000 options. I bet there are other "unique" features, but that's not the point.