Comment 24 for bug 1301125

I wonder if this may be related to bug 1313436.

It happens to me about 10% of the time. Sometimes the lock screen or desktop after logging in is just incredibly slow to draw, but it then recovers. I've also noticed that even though the screen isn't updating, login works properly and even though the screen is black, the mouse cursor is resonspive when hovering over where the different windows on my desktop should be drawing at the time.

I am able to run 'killall -HUP unity' to fix the issue which is probably the same thing as running 'unity --replace'.