Mozilla's CEO has published an open letter of complaint about Windows 10's default browser settings over Mozilla changing users' default search setting in its own Firefox browser. Chris Beard, Mozilla's CEO, has posted an "open letter to Microsoft's CEO" about the way that Windows 10 handles default programs. He is complaining about "the Windows 10 upgrade experience that strips users of their choice" because Microsoft's Edge browser becomes the default after an "in place" upgrade.

"we reached out to your team to discuss this issue. Unfortunately, it didn't result in any meaningful progress, hence this letter," Beard says.

As Mozilla knows, Windows 10 users can change the defaults to whatever they want. However, Beard complains that "it now takes more than twice the number of mouse clicks," and that it's "confusing, hard to navigate and easy to get lost".

However, Mozilla has also changed users' default search engine in the popular web browser some months ago. Firefox forced a search engine switch to Yahoo, and after users reinstated their preference for Google, Firefox updates repeatedly changed it back.

Since the release of Windows 10 24hrs ago, more than 14 million devices are already running Windows 10, according to Microsoft.