14 DAY TRIAL // It may seem like deja vu, but Mozilla is complaining that Microsoft is creating an artificial monopoly for its browser in Windows for ARM by not allowing other apps, including other browsers, to use the full capability of the operating system.
Mozilla says that this essentially gives IE exclusive reign over Windows 8 tablets and other devices that may use ARM chips, as it will be impossible to build a full-fledged browser with only the tools available to third-party developers on this version of Windows.
"Windows on ARM -as currently designed- restricts user choice, reduces competition and chills innovation," Harvey Anderson, Mozilla general counsel, wrote in a blog post.
"By allowing only IE to perform the advanced functions of a modern Web browser, third-party browsers are effectively excluded from the platform. This matters for users of today’s tablets and tomorrow’s PCs," he added.
Windows 8 ARM apps are restricted to the Metro API
To understand the problem, you first have to understand Windows 8 and it can be a bit confusing. Windows 8 will come with two environments for apps.
The first is the classic Win32 one in which apps have access to all the APIs they want, the Windows everyone knows.
With Windows 8, Microsoft is introducing the Metro environment as well, with a new set of APIs and features. The Metro environment is more akin to what you'd get on a mobile platform, like iOS, Android and, yes, Windows Phone.
Apps run in a sandbox, so they don't have direct access to the file system or the hardware, and are only able to use the Metro APIs. These are more than enough for something like Angry Birds, a calendar app, or anything in between, but not enough for a browser.
Traditionally, Windows has only been available for x86 chips, the ones powering your laptop and your desktop. On x86 PCs, any developer can access both the old "classic" environment and the Metro one, in Windows 8.
Mozilla is already working on a Metro version of Firefox, optimized for touch, which uses Metro UI elements.
But, even with the Metro UI, it will still be the same Firefox running underneath with full access to the Win32 API of the classic, desktop environment.
On ARM-powered devices running Windows 8, third-party developers will only have access to the Metro APIs, so they won't be able to run any existing desktop app, including Firefox, Chrome, Photoshop and what have you, even if they have a Metro UI version.
Microsoft though will allow IE and a handful of its own desktop apps to access the full Win32 API on AMR devices, meaning the same IE will run on both x86 and ARM devices.
Microsoft has already been in trouble for restricting browser options
Mozilla believes this is unfair since it sets up IE as the only browser option on Windows 8 tablets and on future devices powered by ARM chips, be them light laptops or all-in-one desktops.
"We encourage Microsoft to remain firm on its user choice principles. Excluding 3rd party browsers contradicts Microsoft’s own published Principles that users and developers have relied upon for years. These principles represented a Microsoft market approach that was both notable and went above and beyond their DOJ antitrust settlement obligations," Mozilla writes.
Microsoft has gotten into trouble over this before and has fought antitrust lawsuits in both the US and the EU. In Europe, Microsoft was forced to stop bundling IE with Windows and allow users to choose between several browsers after they installed the operating system. Antitrust regulators on both sides of the Atlantic may not be too happy about this turn of events.
Update: Google is not happy about Windows 8 for ARM browser limitations either, but it only occured to it after Mozilla spoke up.