This article was written and published in April 2019 and will no doubt be dated by 2020, perhaps by mid-summer 2019. Keep that in mind.
I've been using the new Microsoft Edge browser for the last week. Microsoft kept the name "Edge" but just about everything else has changed.
The user interface isn't actually all there yet and it's clear that things are changing, but the key change is the adoption of a different browser engine. The browser engine is the browser's brains: among other things, it converts the code on remote servers to nice web pages that you can read in your browser. In the old Edge, Microsft used a proprietary engine called EdgeHTML. It worked pretty well--I'd say, about as well as the WebKit rendering engine used by Apple's Safari browser. But, notwithstanding what appears to be the massive advantage of being the default browser on every Windows 10 PC sold in the world, the original Edge browser never caught on.
There seem to me to be two reasons for that failure. First, Edge was released as a part of Windows 10, and the PC world didn't rush to upgrade to Windows 10. The other reason for Edge's failure to achieve the dominance its predecessor, Microsoft Edge had, is that Edge appeared on the scene right around the time that Google Chrome was achieving dominance. As a result, plug-in and extension developers flocked to Chrome, with the result that Edge users had available to them only a fraction of the plug-ins available to Chrome users. Equally bad, some of those plug-ins that were ported to Edge didn't work as well in Edge as they do in Chrome. (This is certainly true for password managers LastPass and 1Password.)
Anyway, something needed to be done.
IF YOU CAN'T BEAT 'EM, JOIN 'EM
So Microsoft kept the name "Edge" and threw out everything else, replacing the old rendering engine with the Chromium engine that underlies Google Chrome. My impression is that all of the major browser engines (WebKit for Safari, Quantum for the latest Firefox, and Chromium) are pretty good and it's certainly true that each has its cheerleaders. But it's undeniable that two thirds of the browsers in use on the Web today are based on the open-source engine Chromium: Brave, Opera, Vivaldi and Chrome, as well as others. So Chromium's impact on the web is massive. That alone makes it a good choice for Microsoft to have picked and since Chromium is open source, Microsoft is now in a better position to get back to having a big say in the direction the internet is moving. On an immediate practical level, extensions that work with Chrome should now work with the new Edge, a fact that eliminates one of the principal reasons Windows 10 users have for switching to Chrome. And since, as the maker of the world's most widely used operating system, Microsoft has a huge marketing advantage, not to mention that Google has a lousy reputation in the privacy department, I suspect the new Edge will do much better than the old one did.
THE NEW EDGE IS VERY GOOD
To be honest, I liked the old Edge and used it fairly regularly. I liked the UI and the old Edge felt more secure--and less invasive of my privacy--than Chrome.
But the new Edge is very good. I'm not a browser-phile who runs benchmark tests. I am however a pretty attentive user who is interested in pages rendering properly, in extensions working properly, in pages loading reasonably quickly, and in a clean and easy to use program interface. Edge scores well in all these areas. Even though it's still a public beta and the UI isn't all there yet, the new Edge has already replaced Chrome for me in daily use.
But the new Edge has not replaced Firefox or Brave for me--not yet. I'm very fond of a number of Firefox's unique features; the Notes app in the sidebar is a particular favorite of mine. I like Firefox for its privacy and frankly for its independence and I like Brave for the same reasons. We'll see how Edge stacks up in those respects when the final version is released.
Still, this is a very promising start.