The Display Server Problem
Modern versions of Ubuntu Linux use “Wayland” as the default display server architecture, completely replacing the decades-old X11 (Xorg) system. While Wayland is significantly more secure and offers smoother graphical performance, its strict security model actively prevents applications from reading pixels outside of their own window. Because of this, many older applications—specifically screen sharing tools like Discord, Zoom, Microsoft Teams, and TeamViewer—will completely crash or display a solid black screen when you attempt to share your desktop during a meeting. To fix this compatibility nightmare, you must force Ubuntu to abandon Wayland and boot using the legacy X11 server instead.
How to Force X11 on the Login Screen
You do not need to uninstall Wayland; you can simply select X11 as your session type right before you log in.
- Restart your Ubuntu machine or completely Log Out of your current session.
- On the graphical login screen, click your username so the password field appears.
- Look in the bottom-right corner of the screen for a small Gear icon. Click it.
- A small menu will appear showing two options: “Ubuntu” (which is Wayland) and “Ubuntu on Xorg”.
- Select Ubuntu on Xorg.
- Type your password and log in normally.
Verifying the Change
The visual desktop environment will look exactly the same. However, you can verify the change by opening your Terminal and typing echo $XDG_SESSION_TYPE. It should now output x11 instead of wayland. Because X11 allows global screen reading, your screen sharing applications (like Discord and Zoom) will instantly begin functioning perfectly. Ubuntu will remember your choice; it will continue to boot into X11 every time you turn the computer on until you manually select Wayland from that gear menu again.