Jump Desktop doesn't refresh the screen on iPadOS when is connected to external monitor

Hello,

When I am connected to a remote desktop (Ubuntu) throught a VNC connection all works perfectly, until I connect the external screen with a 3440x1440 resolution. The image is projected into screen and I can see the pointer, but then the image is nevers refreshed anymore until I disconnect the monitor.

I think that could be a bug, but I don't understand where it could come.