Graphical artifacts on my Mac's screen.

Hello, dear experts. Upon restarting my laptop I ended with a display artifact stretching right from the top to the bottom of my screen, occupying somewhat about 10 percent of it. Sometimes it's just plain gray, but at times in changes its colors, copies the background or folders I open, Safari pages, etc. Strangely enough, it occurred with no visible reason as I had worked on my laptop before that day, and nothing of this sort was the case. No damage was done to the machine whatsoever.

Here's a list of what I did in order to fix the situation:

• Apple Diagnostics: no issues found.
• Safe mode: no effect.
• NVRAM and PRAM: you guessed it.
• SMC: the same.
• Adjusting display resolution or other settings: no.

I've also looked into a couple of forum discussions. Turns out it's a recurrent problem that might have something to do with the insides of the laptop.

What do you suggest?

Thank you.