Firefox

I hope it's optional. I dislike it in both the taskbar and browsers. I sometimes open the same source from different origins and I'd not be pleased if they come grouped together.

I just use several windows on several virtual desktops. It's much less cluttered.

Those hacks are needed because windows can't handle many things at once.

Ok. Just let me know when it's available I guess?

Finally!

Chrome's only had this for like four years