Earlier this week, it was reported that Microsoft is adopting Chromium in its in-house Edge browser, effectively killing its rendering engine, EdgeHTML. Today, it's official, as the company has announced that Edge will now be based on the open-source browser.
Microsoft is framing the change as a way to make the internet more compatible for everyone, with less fragmentation. The company is committing to contributing to Chromium, which will have an effect on other browsers as well, most notably Google Chrome, but also Opera, Vivaldi, and others. The firm also says that it will continue to provide backward compatibility with IE-only sites, which aren't that uncommon for business users.
But perhaps most interesting is that Microsoft says that "Edge will now be delivered and updated for all supported versions of Windows and on a more frequent cadence." This means a few things. For one thing, all supported versions include Windows 7 and 8.1, and the firm even said that it plans to bring its browser to macOS. This also means that Edge will finally be separated from the OS, and on Windows 10, it will probably be updated through the Microsoft Store.
Another thing that Microsoft mentioned a few times is that it's working on bringing ARM64 support to Chromium, something that's been noticed already. That means that along with Edge, we should see ARM64 support for other Chromium-based browsers.
What Microsoft didn't mention is how it will handle things that are Edge-specific. For example, if you stream Netflix through the browser, your only option for 4K streaming is Edge; everything else on Windows will get you 720p, except for Internet Explorer, which is 1080p.
More answers will surely be coming soon. Microsoft says that it will have its first preview build ready to test in early 2019. Presumably, it will be ready for prime time shortly after that, as we only have until January 2020 before Windows 7 is no longer classified as a supported version of Windows.