Kali Linux: How to fix Flickering in some versions of Linux on VirtualBox
Some recent versions of Fedora and other desktop environments run a version of Gnome that has Wayland display server instead of GNOME XOrg. This can introduce a screen flicker which is most noticeable on VirtualBox especially on macOS.
This is easy to fix. You just need to switch back to XOrg and make it your default display server. Naive Approach
The naive approach is to select the display server from the log-on screen.
Start the computer Select the user session Click the gear icon located next to the Sign In button In the dropdown select the option with XOrg Enter your password and Sign In
This is a per-user approach, which means each user will need to do that to fix the flickering. Permanent Solution
A more reliable solution for all is to change the GNOME Desktop Manager configuration to disable Wayland.
This is a global change and will be applied to all of the users immediately.
Open /etc/gdm/custom.confin a text editor Find WaylandEnable property, make sure that it is set to false and that the line is not commented out. Or you can set the default display server by adding this line under [daemon] DefaultSession=gnome=xorg.desktop Save the changes and restart the computer.
Congratulation! You have fixed the flickering.