Problem with graphics after wake-up

[Sportpoz]

For some time I have been experiencing graphics problems after waking up the Macbook periodically. It is revealed as in the picture ...
You can see white vertical bars from top to bottom and a square instead of the cursor.
Since yesterday, I had such a problem twice.
I have a Macbook Pro without TouchBar - graphics Intel Iris Graphics 540 1536 MB
system: macOS - 10.14.2 - but it also happened on an earlier one

 

[4now]

I've seen it 3 times on my 4 month old Macbook Pro (2018), after opening the lid.
I can move the (square) cursor around.
It usually clears before I can even take a picture.

I had upgraded to Mojave when I first noticed it, and the last thing I did was watch a video.. or the very last time screen-record was left running (that was an accident).