It's official: Microsoft is indeed moving their Edge browser to Chromium as previously reported. Windows VP Joe Belfiore made the announcement yesterday with a blog post entitled "Microsoft Edge: Making the web better through more open source collaboration".

The post begins as follows (emphasis added):

"For the past few years, Microsoft has meaningfully increased participation in the open source software (OSS) community, becoming one of the world’s largest supporters of OSS projects. Today we’re announcing that we intend to adopt the Chromium open source project in the development of Microsoft Edge on the desktop to create better web compatibility for our customers and less fragmentation of the web for all web developers.

As part of this, we intend to become a significant contributor to the Chromium project, in a way that can make not just Microsoft Edge — but other browsers as well — better on both PCs and other devices."

Not an immediate move, the under-the-hood changes to the Microsoft Edge browser will take place "over the next year or so", with the transition described as happening "gradually over time". From Microsoft:

1. We will move to a Chromium-compatible web platform for Microsoft Edge on the desktop. Our intent is to align the Microsoft Edge web platform simultaneously (a) with web standards and (b) with other Chromium-based browsers. This will deliver improved compatibility for everyone and create a simpler test-matrix for web developers.

2. Microsoft Edge will now be delivered and updated for all supported versions of Windows and on a more frequent cadence. We also expect this work to enable us to bring Microsoft Edge to other platforms like macOS. Improving the web-platform experience for both end users and developers requires that the web platform and the browser be consistently available to as many devices as possible. To accomplish this, we will evolve the browser code more broadly, so that our distribution model offers an updated Microsoft Edge experience + platform across all supported versions of Windows, while still maintaining the benefits of the browser’s close integration with Windows.

3. We will contribute web platform enhancements to make Chromium-based browsers better on Windows devices. Our philosophy of greater participation in Chromium open source will embrace contribution of beneficial new tech, consistent with some of the work we described above. We recognize that making the web better on Windows is good for our customers, partners and our business – and we intend to actively contribute to that end.

The full blog post from Belfiore is available here.