Drag and drop is not supported with Wayland desktops

If the shared screen runs on Wayland, the drag and drop file transfer built in NoMachine does not work.

File transfer is possible via the !M menu: click on the !M icon in the system tray of the remote desktop to open it. The 'Send a file from the client' and 'Download a file from the server' options will allow to upload a file from the local computer to the remote desktop or download a file from remote to locale.

See: https://www.nomachine.com/DT10O00156#10

As an alternative to the !M icon, open the NoMachine Service User Interface on the remote desktop and access the Connected users panel. Click on the 'Show the whiteboard' option at the bottom end of the GUI. The whiteboard tool provides the 'Send a file' and 'Download a file' buttons.