The developers of both Chrome and Firefox committed to developing Metro-style versions of their browsers; while Chrome's "Windows 8 mode" uses a full-screen version of the existing desktop interface, Firefox's version (which was first made available on the "Aurora" release channel in September 2013) uses a touch-optimized interface inspired by the Android version of Firefox. In October 2013, Chrome's app was changed to mimic the desktop environment used by Chrome OS. Development of the Firefox app for Windows 8 has since been cancelled, citing a lack of user adoption for the beta versions.

Which two browsers promised to develop Metro-style versions of their browsers?