I have the same problem, but it only happens to be on startup. My system is set to automatically log in.
When I first turn on my machine, it logs in and I am able to launch programs etc. after a short while (maybe a minute or two) I notice some strange graphical artifacts near the top of the screen, it is hard to describe but something along the lines of a few rows of blinking rectangles. I then get logged out, after which I can log back in and I have no further problem.
I have no idea what package might have caused this.
I have the same problem, but it only happens to be on startup. My system is set to automatically log in.
When I first turn on my machine, it logs in and I am able to launch programs etc. after a short while (maybe a minute or two) I notice some strange graphical artifacts near the top of the screen, it is hard to describe but something along the lines of a few rows of blinking rectangles. I then get logged out, after which I can log back in and I have no further problem.
I have no idea what package might have caused this.