I had the similar problem and on my research found that it's intel new graphic update problem. I was able to solve my issue by issuing following commands on my terminal.
sudo apt purge xserver-xorg-video-intel
After issuing the command, it is recommended that you restart your pc but logout and log back in may also work fine. I hope this will be able to ...
The Intel Graphics driver's preinstalled in the kernel.
https://www.linuxbabe.com/desktop-linux/switch-intel-nvidia-graphics-card-ubuntu shows sudo prime-select intel switches back to Intel and prime-select query shows which card is active.
More detail at https://askubuntu.com/a/661924/197910
I think I found a way out of this mess by upgrading to Ubuntu 20.04!!
Before attempting to upgrade, I removed weird non-proprietary PPA's, like oibaf, and rebooted (should probably have purged them instead of just removing).
I following the official guide here to upgrade from 18.04 to 20.04:
To configure screens with xrandr
Here is a script for using xrandr to modify one display to use fractional scaling while the primary does not scale. Take this and modify it to fit your needs.
xrandr --output DP-1 --off --output HDMI-1 --off --output DP-2 --off --output HDMI-2 --off --output DP-1-1 --off --output DP-1-2 --off # --output eDP-1 --off --...
This solution also works for Ubuntu 20.04. The xserver-xorg-video-intel that came with 20.04 breaks some Intel graphics cards, including mine (Mesa Intel HD Graphics 510). All sorts of weird visual effects, including not being able to see or click on the window that was on top (instead, a black translucent box). To solve this, first I uninstalled the new ...