What is this display glitch? Has anyone seen anything like this one?

@raid1337 I have seen this momentarily on some MacBooks when shutting down too, I think it is a bug with how the OS deals with colour when waking or shutting down. Try what Dan says to see if this resolves the issue

@reecee - All of our systems do this when the user account is changed and we set the logout timeout for 2 minutes forcing people to re-login to their systems (tight security here).

The blur effect is to hide what you have open but still leave the screen with the active on the desktop so the screen does not need to refresh what you have. You can see it when you alter the user account just pick someone in the list and you'll see the blur, just hit cancel to get back to your screen.

@danj To be honest my problem isn't that after sleeping it requires immediately a password. That's what I want it to do. But the random color, spilled ink-like shaped figures that disappear after a few seconds without touching anything are the ones what I trouble about. My problem isn't the blur effect

@danj no, I was talking about the effect @raid1337 mentions in the video, not the blurring.

@raid1337 this effect can be seen on MacBooks or iPads with bad LCD cables, which resolves itself when the cable is moved or prodded, but I don't think this is the problem in your case. As I mentioned in my previous comment, I have seen this happen on MacBooks when shutting down (just before the screen goes black), but I am not sure why this happens. I think it is just an issue with the OS not smoothing the colour in certain scenarios, so it is not a hardware issue, unless it appears/disappears when the screen is moved at certain angles.

@reecee I don't think its the screen cable's fault too, because this one is like 3 days old. Here's another video when it appears/disappears without moving the lid. It does occur quite often, but doesn't occur every time when I wake up the mac.