Trying the Modern UI-infused nightly is pretty simple. Head to the Firefox Nightly page, grab the standard Windows installer, and let it do its thing. When you're prompted to make Firefox Nightly your default browser, say yes. A blue "Nightly" tile will then appear on your Windows 8 Start screen. (Yes, you do have to make it your default browser; otherwise, a different Modern UI tile will show up, and that one will simply open the desktop version of Firefox.)
Modern UI shows up in latest Firefox nightlies
Posted on Friday, Feb 15 2013 @ 14:02 CET by Thomas De Maesschalck
The Tech Report spreads word that Mozilla's Metro-style user interface is now included in the latest Firefox nightly builds. If you want to give it a try, you can download the latest nightly releases of Firefox over here.