GNOME 49 has removed support for Xorg/X11 in favor of the newer Wayland display server.
Linux distributions which adopt GNOME 49, such as Ubuntu 25.10 Questing Quokka, Fedora 43 and any other distro that will adopt it in the future will rely on the newer Wayland display server which completely drops the X11 backend.

As a result, NoMachine virtual remote sessions that rely on X11, no longer work with the GNOME 49 desktop environment. Users who use GNOME 49 will not be able to start virtual desktop sessions through NoMachine. Physical sessions, however, will continue to work as before as NoMachine fully supports Wayland in physical sessions.

If you need to run virtual sessions, in the meantime there are several possible solutions:

1. Install another desktop environment compatible with X11, such as MATE, KDE Plasma or XFCE.

2. Use an earlier version of GNOME, prior to version 49, which still supports Xorg.

3. Stay on an earlier version of your Linux O.S. like Ubuntu earlier than 25.10 or Fedora earlier than 43, where Xorg is still included.

4. Some Fedora 43 users reported to have restored X11 support according to: https://copr.fedorainfracloud.org/coprs/frantisekz/GNOME-X11/

NoMachine will continue to monitor these changes in Linux distributions and provide updates regarding work in progress about future compatibility and full support for Wayland-native virtual desktops.