That is strange, what you said wasn't the problem here... here is a video of what I said: And about customizations, the only one I can think of is the CSSU. The only different things I did that's apart from only installing programs is swappolube and setting CSSU to be blurless with faster transitinos... http://www.youtube.com/watch?v=veQSKmOeRZs Thank you! EDIT: Other 2 shots with the same problem - NOW with FapMan. I could reproduce it with the apps in either position and I have a task switcher set to 2 columns. And there's a black line on the top: