Microsoft has altered Windows 10 so that users have to explicitly set a default app for applications like mail, calendar, or web browsers. The change means the setup installers for Chrome and Firefox can no longer set themselves as the default browser during the install process. Mozilla isn’t happy with this change, and the company is calling on Microsoft to reverse what it calls an "aggressive move to override user choice on Windows 10."

In a blog post and open letter to Microsoft CEO Satya Nadella, Mozilla CEO Chris Beard outlines the company’s concerns. "It now takes more than twice the number of mouse clicks, scrolling through content and some technical sophistication for people to reassert the choices they had previously made in earlier versions of Windows," claims Beard. "It’s confusing, hard to navigate and easy to get lost." Mozilla has created a video to demonstrate the amount of clicks required to set Firefox as the default browser.

If an app like Chrome or Firefox wants to set itself as the default it can still generate a pop-up on first launch, but it now throws a Windows 10 user to a new settings page to then choose the actual default app. Mozilla’s argument that this is more complex is fair as there are more steps to take to actually change your default browser and it will likely generate confusion among some consumers. It’s not exactly clear why Microsoft changed this behavior, but the company did justify it as a way to reduce "some of the unwanted noise that multiple prompts can bring" during the testing of Windows 10. The reality is probably more security-related to ensure apps can’t hijack default settings, and also a slightly devious way to ensure Microsoft Edge remains the default browser. Either way, it’s a user unfriendly change from Microsoft.

Mozilla claims it has reached out to Microsoft to discuss its concerns, but "it didn’t result in any meaningful progress" so Beard was forced to pen an open letter. Mozilla voiced similar concerns over Microsoft's browser changes with Windows RT back in 2012. "We strongly urge you to reconsider your business tactic here and again respect people’s right to choice and control of their online experience," says Beard. "Please give your users the choice and control they deserve in Windows 10."

Microsoft has responded with the following statement: "We designed Windows 10 to provide a simple upgrade experience for users and a cohesive experience following the upgrade. During the upgrade, consumers have the choice to set defaults, including for web browsing. Following the upgrade, they can easily choose the default browser of their choice. As with all aspects of the product, we have designed Windows 10 as a service; if we learn from user experience that there are ways to make improvements, we will do so."

Update, 7/30/15, 8:30PM ET: Added statement from a Microsoft spokesperson.

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