Did your navigation buttons suddenly lose their transparency and return to being white on black? Here’s how I fixed mine.
I’m running KitKat 4.4.4 on my Nexus 5 with the nice transparent status bar and navigation buttons. This enables my wallpaper to extend all the way to the top and bottom of the screen.
However, for some reason, the navigation buttons suddenly turned black. I tried switching from Nova Launcher, which I normally use, to the Google Now Launcher, but that didn’t make any difference. I tried powering off the phone and back on. No dice. I tried choosing other images as the wallpaper to no avail. Next, I scoured the web for a solution and found all kinds of things from rooting the phone to changing various configuration files. Nothing worked.
Finally, I ran across a thread on the XDA-Developers forum that did work. Instead of using the standard Gallery app to set the phone’s wallpaper, use a different app. In my case, I used ES File Manager and its image viewer to open the image I was originally using and set it as my wallpaper. Apparently, the Gallery app doesn’t scale the wallpaper correctly, although it worked back when I originally set a photo to be my wallpaper.
Ah, computers. Whether on your desk or in your pocket, they’ve all got their issues.