Mozilla hits Microsoft with complaint about Windows RT browser choices

Mozilla complained Wednesday that Microsoft prohibits running any browser except Internet Explorer (IE) on Windows RT, hampering choices for users. Google said on Thursday it shares the concerns.

Windows RT, the version of Windows 8 that runs on devices using an ARM processor, restricts user choice, reduces competition and chills innovation said Harvey Anderson, Mozilla General Counsel in a blog post. By only allowing Internet Explorer to fully access advanced OS functions, "third-party browsers are effectively excluded from the platform," he said.

Windows RT will have two environments, one the app-tailored Metro environment aimed at tablets and phones, and a classic Windows interface. Microsoft allows only Internet Explorer to run in that classic environment, Mozilla said. In practice, this means browsers like Firefox, Chrome and Opera will not be able to access "vital" advanced computing functions that enhance speed, stability and security of those browsers and, according to Mozilla. The company argues that if Microsoft's Internet Explorer can run on Windows RT, there is no technical reason to conclude other browsers can’t do the same.

The exclusion of other browsers is going to affect users of tablets and will possibly have an effect on PC users in the future, Mozilla said. According to the browser maker it is not unthinkable that ARM chipsets that are mainly used in phones and tablets today will eventually be used in PC hardware platforms. "It’s easy to imagine Windows running on ARM in laptops, tablets, phones, and a whole range of devices. That means users will only have one browser choice whenever there’s a Windows ARM environment," Mozilla said, adding that the world does not need another proprietary environment.

Mozilla called on Microsoft to "remain firm on its user choice principles," warning that the exclusion of other browsers may have antitrust implications. Mozilla said Microsoft could violate the browser choice rules set by the European Commission (EC) and seems to represent behavior that a U.S. settlement sought to prohibit. "We do not plan to file formal complaints at this time," a spokesperson for Mozilla said in an email. Mozilla will continue to evaluate the situation, however, and see if filing formal complaints in future may be the appropriate mechanism to get the resolution that the company is after.

Chrome-maker Google on Thursday weighed in on Mozilla's complaint. “We share the concerns Mozilla has raised regarding the Windows 8 environment restricting user choice and innovation," Google said in an emailed statement. In the end, consumers and developers benefit the most from robust competition, it added.

Microsoft did not immediately respond to a request for comment.

Loek covers all things tech for the IDG News Service. Follow him on Twitter at @loekessers or email tips and comments to loek_essers@idg.com