What's the deal with this "Ubuntu Browser" being set as the default?
I feel like Canonical has a serious Not Invented Here problem, where they keep trying to re-invent the wheel by writing their own desktop environment, window manager, browser, startup system, etc.
Rebranding stuff isn't Not Invented Here syndrome. Relax. They didn't re-invent anything. It's just Firefox with a few patches for integrating with their desktop environment.
Plus, they gave up on their startup system. They'll be switching to systemd in future releases.
It seems we were both wrong. Forhackernews was most likely referring to the new web app system. Websites that register themselves as web apps get their own launcher icons, run in their own window, show desktop notifications, etc., and they're powered by Ubuntu's custom QML-based browser which is referred to as Ubuntu Browser.
Firefox is still there, and still branded as Firefox. Ubuntu Browser isn't intended to replace it outright.
I feel like Canonical has a serious Not Invented Here problem, where they keep trying to re-invent the wheel by writing their own desktop environment, window manager, browser, startup system, etc.