To quote Mozilla:
"On Windows 8, IE10 is both a metro app and a regular desktop application. When run as a metro app it does things that are known to be off-limits for metro applications."
So Mozilla is looking to Microsoft to provide it with the same privileges as Internet Explorer has. Put another way, Firefox needs to run as a Medium level integrity process with full use of the Win32 API.
"In general, browser vendors would prefer access to the system similar to that of Internet Explorer 10. From all outward appearances IE is currently able to bypass security restrictions of the Metro sandbox by running as a medium integrity process, effectively running as a standard Windows desktop application with additional extensions which allow it to latch into the Metro interface.
Vendors feel changes should be made to the current restrictions which will facilitate the ability of 3rd parties to compete with Microsoft's products in this new environment."
Of course this is not just a problem for Mozilla — both Google and Opera are going to want equal treatment, as are the makers of any other type of app that Microsoft decided to include as a MetroTop app.
What if Microsoft says no?"
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