I had been experiencing problems with the glitched screen since I installed Manjaro.
The problem had been happening when I got my laptop suspended (automatically or either manually) and then tried to wake it up. I saw a screen like this:
After some time I found out that I have Wayland enabled (I tried to restart the screen by doing alt+f2 and entering r command. But it can’t be restarted during a wayland session.)
So I decided to try to disable wayland and see what’s going to happen. To my surprise, wayland was the actual issue!
I disabled it by uncomment WaylandEnable=false in /etc/gdm/custom.conf. After that, I rebooted my system. Suspended it, woke it up, and there were no glitches at all!
IDK what a Wayland is and why it was enabled by default. But I hope it might be a help for someone.