Every time I install ubuntu on a laptop and close the lid (I think it goes to sleep then). If I open the lid again the background image is black or very weird like this:
I am using ubuntu 19.04. I don't know if this is relevant but this is my gpu: GeForce 940MX/PCIe/SSE2
Does someone know how I can fix this. My laptop is completely usable and I feel stupid for asking this. But if someone knows how to fix this please let me know.
Thanks in advance!