Sony has pledged support to the upcoming Firefox OS and had announced that the company would release phones running the OS once it is fully ready. Now the company has gone one step ahead and released a Firefox OS ROM for the Xperia E. The ROM isn’t just for everybody though, but is intended for developers and enthusiasts in order to get some feedback regarding the OS. In fact installing the OS requires rooting the device which may void the warranty.
Sony has provided a detailed procedure for those still keen enough on getting the new OS on their handsets. However since this is just an experimental version the radios won’t work, meaning no calls or internet over WiFi. Along with that Sony also warns that the SD card functionality might be unstable and even the touch screen hasn’t been calibrated properly.
If you’re still want to go ahead with the installation, this video could be of some use to you. You can also visit the official Sony page that provides detailed instructions here.